EkmekciF. N., and TuğG. “Notes on the Lightlike Hypersurfaces Along Spacelike Submanifolds”. Ukrains’kyi Matematychnyi Zhurnal 71, no. 7 (July 25, 2019): 968-975. Accessed September 27, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/1490.