1.
Belkhelfa M, Mahi F. Second order parallel tensors on $S$ -manifolds and semi-parallel hypersurfaces of $S$ -space forms. Ukr. Mat. Zhurn. [Internet]. 2019Oct.25 [cited 2022Oct.6];71(10):1422-9. Available from: http://umj.imath.kiev.ua/index.php/umj/article/view/1524