@article{1103039899, author = {Reid, William T.}, title = {A Pr\"ufer transformation for differential systems.}, journal = {Pacific J. Math.}, volume = {8}, number = {4}, year = {1958}, pages = { 575-584}, language = {en}, url = {http://dml.mathdoc.fr/item/1103039899} }
Reid, William T. A Prüfer transformation for differential systems.. Pacific J. Math., Tome 8 (1958) no. 4, pp. 575-584. http://gdmltest.u-ga.fr/item/1103039899/