@article{1183513481, author = {Kosambi, D. D.}, title = {The differential invariants of a two-index tensor}, journal = {Bull. Amer. Math. Soc.}, volume = {55}, number = {12}, year = {1949}, pages = { 90-94}, language = {en}, url = {http://dml.mathdoc.fr/item/1183513481} }
Kosambi, D. D. The differential invariants of a two-index tensor. Bull. Amer. Math. Soc., Tome 55 (1949) no. 12, pp. 90-94. http://gdmltest.u-ga.fr/item/1183513481/