K.  Wada, ?Laminary structures of cultured pearls observed with electron microscope - I. Nacreous layer pearl?, Bulletin of the Japanese Society of Scientific Fisheries, vol. 23, pp. 302-305, 1957.

K.  Wada, ?The crystalline structure on the nacre of pearl oyster shell?, Bulletin of the Japanese Society of Scientific Fisheries, vol. 24, pp. 422-427, 1958.

K.  Wada, ?Laminary structures of cultured pearls observed with electron microscope - I. Nacreous layer pearl?, Bulletin of the Japanese Society of Scientific Fisheries, vol. 23, pp. 302-305, 1957.

K.  Wada, ?The crystalline structure on the nacre of pearl oyster shell?, Bulletin of the Japanese Society of Scientific Fisheries, vol. 24, pp. 422-427, 1958.