Real -Life Kantei of swords , part 8: Oei Bizen Swords - What we read and what we see.

W.B. Tanner and F.A. B. Coutinho

Introduction

There is already much written about Oei Bizen swords from a kantei and smith perspective. This article will not attempt to add anything new to the dialogue about this era or try to bring up any new theories or controversial hypothesizes, however we will compare a number of “Oei Bizen” blades from different smiths and try to understand what makes these blades in fact “Oei Bizen” and what the student could expect to find in the kantei of Bizen blades of this era. In a subsequent article we will also discuss the kantei of two potential Oei Bizen Tantos which appear to be nearly identical and were subject to kantei multiple times with differing results and hopefully shed some light on why this particular kantei was so difficult. Attributions varied between Oei Bizen and Yamashiro Sanjo Heianjo mono.

Schools to be considered

What is considered in this article are Oei Bizen blades made in the Osafune area during the time period from late Nambokucho to middle Muromachi (Joji 1362 – Eikyo 1441). (5) During this 60-80 year time period there many changes going on both in the ruling of Japan and in the production of Bizen blades. From a political perspective Japan had just exited a turbulent time when the empire was divided between north and south courts and the swords at that time were wide, long and flamboyant. Masterpieces of strength! Now they were entering into a time of relative peace, just before the beginning of the 100 year war period (Sengoku). With that relative peace, Bizen smiths were able to focus on producing swords of a more varied nature without the pressures of wartime production demands. It was during this time that the Oei Bizen mono developed.

During the Oei era several schools existed in the Osafune area, for example: Kozori, Omiya, Yoshii and Hatakeda schools. All were considered parts of the Osafune style, which indeed dominated their workmanship. There are, however, differences and not all works conformed exactly to the style of the main Oei Bizen smiths. (5) Also there were smiths who moved into the Osafune area, such as Yukikage, who brought with them styles from other areas.

This article will focus on a narrow group of Osafune Bizen smiths and school – i.e. the “Three Mitsu” (Yasu, Moro, Mori) and the Kozori school from Osafune. However, for comparison purposes we will discuss one Hatakeda blade , two Kozori blades, a Omiya blade, a Moromitsu blade and a Yukikage (second generation) blade. This last blade is from a smith who moved into the Osafune area, but was trained in the Oei Bizen style. The purpose of this article is not to explain or generalize on the style of Oei Bizen, but to kantei six different real-life examples of blades produced during that time period and compare their similarities and differences.

Observations on the Kantei Blades

To assist the reader in understanding the review of these blades, it is necessary to understand the terminology used to describe them. Nihonto terminology is often confusing with the use and definitions varying by expert. The terms and definitions we will commonly use are:

Jigane – structure of surface steel

Jihada – texture or patterns found in the surface steel. This is represented by the activity (hataraki) such as Nie, Chikei, and the forging pattern, Itame, Mokume, etc.

Hard and Soft Steel – more related to polishers assessment of the hardness of the steel, but from a visual perspective, does the steel appear to be excessively hardened with lots of Nie and hardened surfaces or not.

Wet jigane – Does the steel seem exceptionally clear and visceral, like it was dipped in water.

Standout (hada tatsu) jihada – is the grain structure highly visible, but not random as in rough or loose jigane The assumption being that the smith intended it to look this way.

Tight/Refined jigane – the structure of the jihada is small and tightly formed patterns. Tight and refined jigane would be a superior form of forging, showing great skill of the smith.

Loose or rough jigane – does the grain structure seem unusually large, random and not tightly welded. The appearance of the jihada may have many large and open patterns in the grain.

Dark and light jigane – dark or black jigane has a bluish or darker reflection to it, light or white jigane

will appear whitish and brighter.

Ko-XXXX – refers to small, i.e. ko-mokume is small and tightly formed mokume patterns.

Although there are many more terms used in describing Nihonto, we will limit ourselves to the above terms and descriptions in describing the steel of the blades. (9)

What is Oei Bizen Style

It is frequently stated that the Oei Bizen mono was a return to the style and sugata of the late Kamakura era, particularly the Ichimonji traditions. However, there were several variations to that tradition that evolved into something rather unique to the era and later carried into the Sue-Bizen mono. Features such as reduced sori, as evidenced by the Kozori smiths, smaller and shorter nagasa and nagako, unique hamon and later as we enter in the Sue-Bizen era a standardized approached to signing, (the familiar Bizen Kuni/Bishu Osafune xxxxxx on the edge of the nagako) are all characteristics of Bizen blades made during that short time period. What didn´t transition into the Sue-Bizen era, was the consistently refined and tight Oei jigane which was generally comprised of mokume with some itame.

Among Nihonto experts, the description of Oei Bizen mono varies slightly.

Nagayama-sensei states that the sugata of Oei Bizen mono is a copy of the tachi sugata of the Kamakura period, but with a shallow sori. He says “the nagasa is comparatively short, the blade is slender, the kasane relatively thick. The blade is compact and handy”. He explains that the jihada is a soft mokume mixed with O-hada and the hamon consists of nioi with a very soft and thick nioi line. The nagako is short and less tapered. (6)

Honma Junji-sensei stated that the Oei Bizen mono produced hamon described as “gorgeous gunome mixed with choji differing from continuous ko-gunome and notare” from the Nambokucho period. He also stated that they produced suguha on their tantos and wakizashi in hira-zukuri which often look like works of AOE at a glance. Another interesting point mentioned is they produced skillfully carved horimono of ken with sankozuka and bonji (the Sue-Bizen mono produced elaborate horimono of kurikara instead). What is important to note is that he believed they produced clear utsuri and soft jigane rather than the more powerful jigane and faint utsuri of the Sue-Bizen mono. (7)

Hinohara Dai of the NBTHK writes:

“The Oei Bizen jihada are itame mixed with mokume, the hada is visible, there are frequent ji-nie and chikei and midare utsuri. Also in either suguha and midare hamon this is often bo-utsuri….the

Oei Bizen nakago tips are a wide kurijiri and the yasurime are katte-sagari” (Shijo Kantei To No 707 – December 2015) An additional hamon development is the “well know koshi-no-hiraita gunome and/or kataochi-gunome” reminiscent of the style of Kagemitsu, Motoshige and the Un group of smiths.

The NTBHK also discussed the development of a Oei Bizen style boshi, referred to as rosoku-boshi or candle flame boshi. Generally we find this boshi on the works of the “Three Mitsu´s”, particularly hira- zukuri blades. This boshi has midare running into the kissaki with a noticeably pointed tip. (8)

The Nihon To Koza points out that although there were minor work style variations among the Oei Bizen smiths, it is difficult to assign clear differences and definitions to each smiths style. However it is clearly stated their style is “modest in comparision to those of the Soden-Bizen, the jitetsu is extremely good.” (5)

Another interesting kantei point on Oei smiths comes from Markus Sesko who writes: “The Kozori smiths adopted the style of the dominating Osafune main line, which was then

represented by master Kanemitsu (兼光), but gave it a trend towards the so-called „koshi-no-hiraita gunome-midare“, i.e. a gunome-midare whose bases (koshi, 腰) are noticeably wider (hiraita,

開いた) as the tips (yakigashira, 焼頭). This trend can be seen for example at Kozori Moromitsu (師光, picture 1).

Picture 1: tachi of Kozori Moromitsu dated Eiwa two (永和, 1376)”

This will become relevant as we kantei the Moromitsu Tanto presented in this article. (10 - 2013/3/13)

One of the interesting things about the Oei Bizen mono is that is not as easily characterized or rigidly defined as the Sue-Bizen mono. It is a transitional style created out of the Nambokucho’s well- defined and powerful sugata transitioning into the characterized style of Sengoku Sue-Bizen period with mass produced and standardized production. This is pointed out by the quote from Homna Junji-sensei in his article on Sue Bizen edited by Elliott Long.

“There is not any particular definition of the term for ‘Sue-Bizen’. Though, it is quite obvious that the term is used for the Bizen smiths who demonstrate a different workmanship from that of the Oei- Bizen smiths and it can be said that their workmanship became more characterized”

Blades to be discussed.

The 6 blades reviewed all have papers either from the NBTHK or NTHK, all are signed (one had the mei removed) and two are dated. All are ihori-mune with a ubu nagako. From the above it may appear that the identification of each smith should be trivial. This is not the case. The papers in each of these cases do not state the generation and directories list many smiths with the same name. Also the directories are not consistent. For example, the first smith listed below ( Bishu Moriiye) technically should be classified as un-listed because the signature Bishu Moriiye is not in the Nihon To Meikan ( 1) . However the NTHK identified him as a smith working around BunAn so it is reasonable to consider him a descendent of the Hatakeda School.

The examples we used are the following:

Hatakeda Mono:

Bishu Moriiye Katana (descendant of Hatakeda school) – NTHK- 5th or 6th generation – BunAn (1444).

Independent:

Bishu Osafune Yukikage Sunnobi Tanto – NBTHK Hozon – Oei era

Traditional Oei Bizen Mono:

Moromitsu Tanto (nijimei -removed) – NTHK –Oei era Iyemitsu Tanto – nijimei – NBTHK Tokubetsu Hozon – Oei era

Bishu Osafune Iyesuke Wakizashi – dated Oei 20 – NBTHK Hozon

Bishu Osafune Tsuneiye Wakizashi – dated Eikyo 6 – NBTHK Tokubetsu Hozon

History of the smiths to be examined

A brief history of each smith, will help understand the differences in their style and why they may or may not fit the traditional definition of Oei Bizen mono.

Yukikage – The sword represented here is from second generation (nidai) Yukikage. It is reported that his father originally came from or also worked in Inaba. However, the Nidai was a student of Yasumitsu of the Three Mitsu´s fame, so technically he should be similar to the mono of Oei Bizen. When we closely examine this blade we see that it doesn´t completely fit into the Oei Bizen mono.

Moriiye – The sword represented here is from the 5th or 6th generation smith Moriiye who was a later descendant of the Hatakeda mono. He worked from late Eikyo until BunAn era. The first generation Moriiye from mid Kamakura era was considered the founder of the Hatakeda mono. The Hatakeda area where these smiths worked was believed to exist within confines of the Osafune area

(11) and is considered a break-off of the Osafune school. Although the later generations of Moriiye no longer possessed the flamboyance of the first two generations, this example of the 5th or 6th generation Moriiye has many characteristic of the Osafune mono of the Oei era.

Moromitsu – This Tanto is attributed to the second generation (nidai) Moromitsu (one of the Three Mitsu´s) and has many distinct characteristics of the Oei Bizen Mono and Nidai Moromitsu.

Iyemitsu – This Sunnobi Tanto is from the first generation (shodai) Iyemitsu son of Ōmiya

Morikage (大宮盛景) of the Bizen Omiya school. (11) We will provide a brief discussion of the Bizen Omiya group later in the discussion. This smith was relatively easy to identify. There are only four smiths with this name listed and this is the only one who worked mainly in Oei .

Iyesuke – This is a shobu-zukari Wakizashi from shodai Iyemitsu of the Kozori group, which according to records is the son of a later generation Nagamitsu (長光) and a student of Kozori Morikage (盛景). An interesting characteristic about this swords is that is Mu-Ku, it has no core. (11) We will provide a brief discussion of the Bizen Kozori group later in the discussion. As mentioned above, the identification of a smith is not so simple. The Hozon paper does not say who he is. Looking at the swordsmith directory by Shimizu (1998), there are eight smiths that signed Bishu Osafune Iyesuke. In this case however only one is said to have worked mainly in Oei era. Since this blade is dated Oei 20 the smith described above is probably correct. In addition, we found an oshigata with a matching signature, which settles the matter.

Tsuneiye – This Wakizashi is from 3rd generation Tsuneiye of the Kozori group. His father was Oei Tsuneiye whose first name was Yajirō (弥次郎) and was the son of Kozori Morikage (小反守景). He worked from 1392 to 1429. Third generation worked from 1429-1452. (Sesko eIndex). Again it is difficult to identify precisely who this Tsuneiye is. In the swordsmith directory by Shimizu (1998) there are five smiths listed . Again only one worked mainly in Eikyo and it was the third generation which was also confirmed by an oshigata. (His father worked until Eikyo 1 )

It is interesting to note that in the older literature (Hawley 1978) the Oei Bizen mono is divided in two branches: Oei Yasumitu and Oei Kozori Morikage. Also there are Iyesukes and Tsuneiyes in both branches.

In the reference books (Homma and Koizume -1994) all the smiths used in this article are considered Atari-Dozen.

Kozori and Omiya School Overviews

The Kozori school was a term applied to groups of smiths who did not follow the mainline Bizen traditions, such as Kanemitsu, Chogi, Motoshige or Yoshii schools, during the Nambokucho era. These smiths utilized a mixture of traditional Bizen style and other styles prevalent at the time, such as Soshu. Some of the famous smiths of this school are Morikage, Morishige, shodai Moromitsu, shodai Tsuneiye, Iyesuke and others. The origin of the term Kozori is somewhat surrounded in mystery, but one popular belief is that it means swords with small Sori, i.e. Ko-Zori. Whether that is true or not is subject to conjecture, however we do know the style that represented Kozori smiths during the Nambokucho era. Kozori swords were made with jigane that was a mix of itame, mokume and nagare that was very visible (stands out), however , the jihada is generally not as refined as mainline Bizen smiths. The hamon is mostly Ko-Notare, or a mix of gunome which may be visibly mixed with choji and togari. Weak utsuri, normally jifu or midare appears on the blades. They also tended towards angular midare gunome and the yakiba is rather narrow in relation to the width of the blade. The boshi tends to be midare-komi or sugu-boshi , ko-maru with a small turn-back (Kaeri). Kozori smiths also tended to sign in larger characters down the middle of the nagako, but not always as demonstrated in various NBTHK Token Bijitsu kantei results.

Towards the end of first decade of the Oei era the Kozori smith´s style evolved into what is commonly referred to as the Oei Bizen mono. It is these later Kozori smith´s blades, such as Iyesuke and Tsuneiye that we are examining.

The Omiya School presents another mystery in the study of Nihonto. Some believe it originated during the middle of the Kamakura era in the Yamashiro area known as Inokuma Omiya. That is where it´s legendary founder Kunimori was from and then later moved to the Bizen area. Others believe that Omiya is a location in Fukuoka where the Omiya smiths lived and worked. In either case it is a branch of the Bizen Osafune school and follows many of the traditions of that school.

Although the school formed in the middle of the Kamakura era and thrived into the Muromachi era, there are no known works from the Kamakura era. Most of the works we have today are from the Nambokucho to middle Muromachi era.

Omiya blades characteristically have tightly forged Itame mixed with mokume and a lively form of choji midare with midare utsuri. The blades tend to be a wilder interpetation of the Bizen Osafune tradition and are sometimes compared to Soden Bizen blades which possess a mix of Soshu and Bizen styles. The jigane is more refined than those of the Kozori smiths, but not of the level of

Kamakura era mainline Bizen smiths. Some of the famous Omiya smiths are Morikage, Morokage, Moritsugu, Iyemitsu and Morishige.

Sword Specifications

Below is a table of the characteristics and specifications of the swords we will examine.

In examining the above chart and from a “paper kantei” perspective there appear to be many similar characteristics of these blades and they seem to fit into the standard Osafune or Oei Bizen mono characteristics. However, closer physical examination of the blades reveals several differences in the color and refinement of the jigane and complexity of the hamon. The depth and clarity of utsuri also

varies by blade, but could be attributed to the polish and condition of the blade. We will examine each blade individually and provide additional commentary based on physical observation.

Yukikage

This Sunnobi Tanto possesses many of the characteristics of Yukikage´s teacher Yasumitsu. It has a classic Oei Boshi, angled midare gunome hamon and visible bo-utsuri. At a glance it looks typical Oei Bizen mono. However on further examination we find that the jihada is much rougher and looser than would be found on a blade from one of the Three Mitsu´s. We also find the jigane is much darker than typical Oei Bizen jigane. Not quite black, but definitely darker. Also, the Hamon interpretation, although typical Oei Bizen style, is not executed as beautifully and lacks uniformity and clarity of the gunome structures and habuchi line. This is clearly an Oei Bizen work, but from a less skilled smith, or a smith who is mixing traditions. When you recognize that Yukikage´s father came from Inaba and practiced a different tradition, you can understand why Nidai Yukikage´s swords are not a perfect rendition of his teacher Yasumitsu.

Moriiye

This later generation Moriiye katana possesses a typical Oei Bizen Sugata. It has noticable koshi - sori, but not the typical saki-sori of the Oei Bizen mono. However, there is more curvature in the last third of the blade than you would find in older blades. Some Nihonto Experts, such as the late Yoshikawa Kentaro, describes swords like this as having both koshi sori and saki sori. (This is the description of the shape of blades in almost all volumes of the Token to Rekishi). There is tapering from the motohada to the sakihada and it possesses a longish kissaki. It also has a large signature down the middle of the nakago. At a glance it looks like a 2/3 size version of a middle to late Kamakura Bizen blade. The short nagasa, more curvature in the last third of the blade compared to older swords, and the nakago are the major giveaways to this being a post Nambokucho blade.

When you look closer at the blade it is apparent this smith is not following the strict Oei Bizen mono. The jigane is an itame mokume mix, more average than refined. The hamon is a classic Bizen traditional gunome and choji mix, but more subdued than the early Hatakeda school hamon. In style it clearly follows the traditions of the earlier Moriiye smith. In fact, when examining a couple of oshigatas from Shodai Moriiye (Kamakura), the similarities in the hamon and sugata are apparent.

However, the boshi is a typical Oei Bizen/candle flame boshi, ko-maru with a point, pointing to an

Oei Bizen time period.

Moromitsu

This blade is a conundrum which we will write about in another article. It has two sets of kantei papers and had the nijimei purposely disfigured beyond recognition. This tanto is a small diminutive blade with refined ko-mokume and itame and distinctive koshi-no-hiraita gunome jidare hamon. It has faint midare utsuri. The boshi is a traditional Bizen with midare and a rounded ko-maru and short kaeri. It does not possess a Oei Bizen boshi. Since it does not possess a Oei Bizen boshi and lacks clear bo-utsuri, the kantei must be based on the hamon and jigane. However, based on the characteristics one could assume this is a much older blade than Oei and possibly the work of Shodai Moromitsu, rather than Nidai.

Iyemitsu

This Omiya Iyemitsu Sunnobi Tanto is a beautiful and stunning work of art. The jigane is tight and well refined, looks wet and sparkles in the light with ko-nie. It is by far the nicest jigane of the blades presented. The jihada is a very fine ko-mokume with a suguha based hamon. The hamon has many small choji structures and ashi and bo-utsuri. The blade has an Oei Bizen boshi, but rendered in suguha. What makes this blade unusual is the jigane. It is a little darker than typical Oei Bizen and much more refined. We would need to look at more Omiya Morikage blades to determine if this was a characteristic of his father and teacher, or an anomaly for this blade. In either case, the blade does possess a typical Oei Bizen sugata and many of the stylistic characters of the Oei Bizen Mono.

Iyesuke

This shobu-zukari wakizashi is probably the most typical Oei Bizen mono blade of the group. It possesses all of the typical Oei Bizen characteristics. It has a classic Oei Bizen boshi, the hamon is koshi-no-hiraita gunome-midare, the jihada is a nice mix of refined mokume and Itame with clear midare utsuri. It aslo has the typical Oei Bizen horimono of a Ken. The only thing that makes this blade unusual is that it is made of a single piece of steel with no core. (mu-ku)

Tsuneie

This long hira-zukari wakizashi from Tsuneiye is also a beautifully forged work of art, better than the average Kozori work. The third generation Tsuneiye was known for his excellent forging and this blade is no exception. It has beautiful wet looking refined ko-itame and mokume mix and jihada with an active hamon of well-defined ko- gunome and ko-choji structures full of hataraki. The hamon is not a typical Oei Bizen style. It is a little more subdued and controlled version, probably closer to what you would find in earlier works of the Kozori smiths. Although you might mistake this for an earlier work, the fact that it is dated makes that impossible. Also it does possess a typical Oei Bizen/Candle Flame boshi and the zaimei signature is down the middle of the nakago.

Conclusion

In analyzing the six blades it was apparent that to do proper kantei you need to view blades in hand and not rely solely on the “Paper Kantei” information. When they were examined in hand, paying careful attention to jigane and jihada, we found many unique characteristics of the jigane, such as color and refinement that would not be visible on paper, or even in pictures. We also started to question the commonly understood characteristics of what is “Oei Bizen mono”.

For example, it is stated by a few Nihonto experts that Oei Bizen blades possess a unique boshi referred to as the rosoku-boshi or candle flame boshi. We did some analysis of this by comparing twenty seven Oei Bizen Blades in the NBTHK Token Bijitsu Kantei series and nine Oei Bizen blades in the Nihon Koto Meisaku shu – JUKKEN and found that with the exception of Yasumitsu, this rule does not apply. In fact 18 of the 36 blades (50%) did not possess this boshi and there was little correlation as to whether they were hira-zukari or shinogi-zukari. However, we did determine that if it was a Yasumitsu blade, then it should have a candle flame boshi (75% did). If it was a Morimitsu, then it generally would not have a candle flame boshi (80% did not). If it was a Moromitsu then it was almost even probability. Other than the “Three Mitsu´s”, there was no rule on who used this boshi and who didn´t. For kantei purposes, we should only consider that a blade with a candle flame boshi, it is most likely an Oei Bizen .

The same applies to the unique hamon (koshi-no-hiraita gunome-midare) that is characterized as Oei Bizen Mono. We found that if a blade had this hamon structure, it could generally be considered as part of the Oei Bizen Mono, but most of blades we reviewed did not have this hamon.

The jigane was complicated by the differences in descriptions used by the NBTHK, NTHK and others. For example, the distinction between mokume and itame is not clear. One expert referred to the blade as having well forged itame and another said the same blade had well forged mokume. In kantei, it is probably best to consider the refinement or tightness of the grain structure, rather than whether it is itame or mokume. In examining the six blades, the refinement level of the jigane did vary, but further analysis would need to be done to determine if it was significantly different than pre and post Oei era Bizen blades.

Another area of confusion was the appearance of utsuri. Some experts stated that Oei Bizen mono needed to have clear bo-utsuri, others stated it needed clear midare-utsuri or either. In our examination of the six blades and review of many kantei results, the utsuri question was never completely resolved. What should be assumed is that all Oei Bizen mono blades should have utsuri. The type and clarity of it will vary by smith and condition of the blade.

Another point of kantei which could be used was the use of horimono on the blades. In the six blades we examined as well as many of the kantei blades we looked at, the use of ken with sankozuka and bonji was very common.

Signature placement is another area of Kantei that should be closely examined. Prior to and during the Oei Bizen era, most of the signatures on blades were placed close to the middle of the nakago, particularly on Tanto and Wakizashi. As we move closer to the Sue-Bizen era, we find the signatures moving to the edge of the Nakago and using a more standardized approach. Only the nijimei (two character) would sometimes remain in the center. The six blades we examined followed this pattern.

An area of kantei that we were not able to verify was the point that Oei Bizen mono blades would be made with saki-sori, rather than the traditional Bizen koshi-sori. This is because only two of our blades had sori. The others are mu-sori. The two blades that have sori, show saki-sori or could be described as having both saki-sori and koshi-sori. The use of the term sori in these cases is not defining the place of the blade that is further way from a line drawn from the tip of the kissaki to the end of the mune machi, it only refers only to curvature. Old swords (kamakura jidai) have little curvature in the last third of the blade compared to muromachi blades. This is not accidental. The muromachi blades were adapted to new and emerging fighting methods on foot, not horseback.

In reviewing the six swords, we realized that many of them came from smiths names that were used by several generations. Where you have multiple generations of the same smith, it is not easy to determine which generation the blade represented. In cases where the blade was signed and dated, we could narrow it down based on the date, or an oshigata, but with mumei blades the process is more complicated. For example, the Moromitsu tanto had many characteristics, such as the boshi and sugata of the first generation blades. These were not characteristics of the second generation. However, the hamon was typical of the second generation, not the first.

In summary, the kantei of Oei Bizen blades is sometimes full of contradictions and anomalies. When you have a signed and dated blade possessing all the characteristics of the Oei Bizen mono, the process and conclusions are apparent. However, as we have seen in the above six examples, these types of blades may prove to be the exception rather than the normal. In most cases, one needs to look very closely at the blade for characteristics of the era and area and then use a process of elimination to narrow it down to a school or smith.

References

1. Homma and Masakuni (POD)-Honma Kunzan and Ishii Masakuni, Nihonto Meikan, Yuzankaku, Tokyo

   
   

2. Shimizu (1998 ) -Shimizu Osamu, Tosho Zenshu, Bijutsu-club, Tokyo

   
   

3. Hawley (1978) - W. M.Hawley , Japanese sword groups , Hawley Publisher, Hollywood

   
   

4. Homma and Koizume ( 1994))- Homma Junji and Koizume Hisao, Nihon To Koza Volume IX,

   Koto Kantei, Part 3, page 348 . Afu Research Enterprises , INC, Texas USA

   
   

5. Honma Junji (1994), Nihon To Koza Koto volume IX Part III (Oei Bizen section), Afu Research Enterprises ,INC, Texas USA

   
   

6. Kokan Nagayama(!998) , The Connoisseurs Book of Japanese swords, Kodansha USA, page 184

   
   

7. Honma Junji , Nihon-koto-shi, 5.14

   
   

8. NBTHK Token Bijitsu Kantei results, 97.642 and others

   
   

9. Markus Sesko, Website Kantei Series, Jigane and Jihada section, (http://markussesko.com/)

   
   

10. Markus Sesko, Website, various dates and blogs, (http://markussesko.com/)

    
    

11. Markus Sesko, eIndex of Swordsmiths