@article{GDZPPN002388588, title = {On solutions of ...V+V = 0 in an exterior region.}, journal = {Mathematische Zeitschrift}, volume = {71}, year = {1959}, pages = {251-257}, zbl = {0092.31402}, url = {http://dml.mathdoc.fr/item/GDZPPN002388588} }
Hartman, Philip. On solutions of ...V+V = 0 in an exterior region.. Mathematische Zeitschrift, Tome 71 (1959) pp. 251-257. http://gdmltest.u-ga.fr/item/GDZPPN002388588/