Readings in Japanese history; Part 2: Annotations
edited and compiled by Joseph K. Yamagiwa; bibliographical introduction by John W. Hall
University of Michigan Press, 1970
 Buku Teks SO
Frellesvig, Bjarke
A history of the Japanese language
Cambridge University Press, 2010
 Buku Teks SO
Nanzan studies on Japanese language and culture
Nagoya, Japan : Department of Japanese Studies Nanzan University
 Majalah, Jurnal, Buletin
International Research Center for Japanese Studies
International Research Center,
 Majalah, Jurnal, Buletin
Miller, Roy Andrew
The Japanese language
University of Chicago Press, 1967
 Buku Teks SO