Švec, Alois Projektive Deformation der Strahlenkongruenzen in mehrdimensionalen Räumen. (Projective deformations of ray congruences in multidimensional spaces). (German) Zbl 0063.09093 Acad. Républ. Popul. Roum., Rev. Math. Pur. Appl. 1, No. 3, 91-92 (1956). Not reviewed MSC: 53-XX Differential geometry PDF BibTeX XML Cite \textit{A. Švec}, Acad. Republ. Popul. Roum., Rev. Math. Pur. Appl. 1, No. 3, 91--92 (1956; Zbl 0063.09093) OpenURL