Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MOMA_1967__71_177392, author = {R.F. Albrecht and P. Vachenauer}, title = {On the {Equivalence} of {Systems} of {Partial} {Differential} {Equations.}}, journal = {Monatshefte f\"ur Mathematik}, pages = {354--368}, publisher = {mathdoc}, volume = {71}, year = {1967}, zbl = {0148.34103}, url = {http://geodesic.mathdoc.fr/item/MOMA_1967__71_177392/} }
R.F. Albrecht; P. Vachenauer. On the Equivalence of Systems of Partial Differential Equations.. Monatshefte für Mathematik, Tome 71 (1967), pp. 354-368. http://geodesic.mathdoc.fr/item/MOMA_1967__71_177392/