On a Certain Property of Closed Hypersurfaces in an EINSTEIN Space. Yoshie Katsurada Commentarii mathematici Helvetici
Some Congruence Theorems for Closed Hypersurfaces in Riemann Space. (Part I: Method based on Stoke's Theorem). Yoshie Katsurada — 1968 Commentarii mathematici Helvetici
Some Congruence Theorems for Closed Hypersurfaces in Riemann Space. (Part II: Method based on a Maximum Principle). Heinz Hopf; Yoshie Katsurada — 1968 Commentarii mathematici Helvetici
Some Congruence Theorems for Closed Hypersurfaces in Riemann Spaces (Part III: Method baser on Voss' Proof) Heinz Hopf; Yoshie Katsurada — 1971 Commentarii mathematici Helvetici