Ishiyama, R., 1952, Studies on the rays and skates belonging to the family Rajidae, found in Japan and adjacent regions. 4. A revision of three genera of Japanese rajids with descriptions of one new genus and four new species mostly occured in northern Japan

Ishiyama, R., 1952, Studies on the rays and skates belonging to the family Rajidae, found in Japan and adjacent regions. 4. A revision of three genera of Japanese rajids with descriptions of one new genus and four new species mostly occured in northern Japan, Journal of the Shimonoseki College of Fisheries 2, No. 2, pp. 1-34