Lee, Hyunjin, Eunmi Pak, and Young Jin Suh. “Hopf Hypersurfaces in Complex Two-Plane Grassmannians With $\mathfrak{D}$-Parallel Shape Operator”. MATHEMATICA SCANDINAVICA 117, no. 2 (December 14, 2015): 217–230. Accessed November 23, 2024. https://www.mscand.dk/article/view/22868.