Riemannian Manifoids Diffeomorphic to the Complex Projective Space. Katsuhiro Shiohama — 1973 Mathematische Annalen
Cut locus and parallel circles of a closed curve on a Riemannian plane admitting total curvature. Katsuhiro Shiohama — 1985 Commentarii mathematici Helvetici
On the Structures of Positively Curved Manifolds with Certain Diameter. Katsuhiro Shiohama; Takashi Sakai — 1972 Mathematische Zeitschrift