Voir la notice de l'article provenant de la source Mathematicac Balkanica website
@article{MABA_2001_15_1-2_a1, author = {V. T. Videv}, title = {Two {Curvature} {Operators} in {Riemannian} and {Lorentzian} {Geometry}}, journal = {Mathematica balkanica}, pages = {7}, publisher = {mathdoc}, volume = {15}, number = {1-2}, year = {2001}, url = {http://geodesic.mathdoc.fr/item/MABA_2001_15_1-2_a1/} }
V. T. Videv. Two Curvature Operators in Riemannian and Lorentzian Geometry. Mathematica balkanica, Tome 15 (2001) no. 1-2, p. 7. http://geodesic.mathdoc.fr/item/MABA_2001_15_1-2_a1/