GRECHNEVA, M. A.; STEGANTSEVA, P. G. On the existence of a surface in the pseudo-Euclidean space with given Grassman image. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 68, n. 10, p. 1320=1329, 2016. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1923. Acesso em: 6 dec. 2025.