- Question of writing the oldest French texts -Global Latin vs Local French- (in Japanese), Journal of the Institute of Language Research, 5, 2000, 1-23, The Institute of Language Research. Tokyo University of Foreign Studies.
- Coordinate conjunctions et and si in Old French, (in Japanese), Gengo Kenkyû, 8, Report of Grant -In-Aid for Educational Improvement, 1997, 1-27.
- Three phonetic changes in the formation of French -Voicing, degemination, diphthongation-, (in Japanese), Furansugo wo kangaeru (Reflections on French), Ed. Sanshûsha, 1998, 288-298.
- Significations géolinguistiques des mots représentant la monnaie et la mesure de superficie dans les actes du sud de la Champagne au XIIIe siècle, Dialectologia et Geolinguistica, 4, 1997, 37-46.
- Geolinguistic significance of words representing currency and unit of estate in medieval charters of southern Champagne, (in Japanese), Studia Romanica, 29, 1996, 51-60.
- Notes on variation of sentence type -Relations between Latin charters and medieval documents of southern Champagne-, (in Japanese), Gengo Kenkyû, 6, 1996, 56-82.
- Surname as a memory, (in Japanese), Flambeau, 22, 1996, 27-41, French Section: Tokyo University of Foreign Studies.
- Frontière linguistique de la Champagne occidentale au XIIIe siècle, Revue de Linguistique Romane, 59, 1995, 117-130.
- Peut-on reconstruire des changements phonétiques à partir des textes médiévaux?, Studies in Humanities, 45.1, 1994, 193-210. Shizuoka University.
- Notes on voice in Old French, (in Japanese), Studies in Humanities, 44.2, 1994, 53-83. Shizuoka University.
- EI > OI > WA en français Pour reconoistre la diffusion du langaige, Recherches Linguistiques pour A. Martinet, 1990, 41-82.
- Dynamism of diphthongs in Medieval Champagne documents: a case study-, (in Japanese), Studies in Humanities, 40, 1990, 129-140. Shizuoka University.
- Systèmes distincts, fluctuations ou variantes graphiques en ancien champenois, La Linguistique, 23/2, PUF, 1987, 87-98.
- Essai pour une nouvelle histoire structurale du vocalisme de l'ancien français, In Honor of Shigeru Takebayashi, Kenkyusha, 1986, 40-53.
- Notes on French diachronic phonology -compensation of vacant grid (cases vides)-, (in Japanese), Flambeau, 10, 1982, 141-149. French Section: Tokyo University of Foreign Studies.