Haider ع. أ. Geometrical invariant element’s in theory 2F- mapping between Riemannian spaces A\(_n\) which have tensors (F)\(^3\)=0. University of Aden Journal of Natural and Applied Sciences, [S. l.], v. 21, n. 2, p. 267–277, 2017. DOI: 10.47372/uajnas.2017.n2.a06. Disponível em: https://uajnas.adenuniv.com/index.php/uajnas/article/view/251. Acesso em: 18 may. 2024.