@article{1103036913, author = {Friedman, Avner}, title = {The wave equation for differential forms.}, journal = {Pacific J. Math.}, volume = {11}, number = {4}, year = {1961}, pages = { 1267-1279}, language = {en}, url = {http://dml.mathdoc.fr/item/1103036913} }
Friedman, Avner. The wave equation for differential forms.. Pacific J. Math., Tome 11 (1961) no. 4, pp. 1267-1279. http://gdmltest.u-ga.fr/item/1103036913/