Rigidity and sphere theorem for manifolds with positive Ricci Curvature. Changyu Xia — 1994 Manuscripta mathematica
Minimal submanifolds with bounded second fundamental form. Xia Changyu — 1991 Mathematische Zeitschrift
Universal bounds for eigenvalues of Schrödinger operators on Riemannian manifolds. Wang, Qiaoling; Xia, Changyu — 2008 Annales Academiae Scientiarum Fennicae. Mathematica