Let M be a real hypersurface in a complex space form M_2(c), c \neq 0. In this paper, we prove that S \phi=\phi S on M if and only if M is pseudo-Einstein.
LIM, DONG HO; SOHN, WOON HA; and AHN, SEONG SOO
"The property of real hypersurfaces in 2-dimensional complex space form with Ricci operator,"
Turkish Journal of Mathematics: Vol. 38:
5, Article 12.
Available at: https://journals.tubitak.gov.tr/math/vol38/iss5/12