Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MOMA_1998__125_4_178819, author = {Klaudiusz W\'ojcik}, title = {On {Existence} of {Positive} {Periodic} {Solutions.}}, journal = {Monatshefte f\"ur Mathematik}, pages = {343--350}, publisher = {mathdoc}, volume = {125}, number = {4}, year = {1998}, zbl = {0899.34028}, url = {http://geodesic.mathdoc.fr/item/MOMA_1998__125_4_178819/} }
Klaudiusz Wójcik. On Existence of Positive Periodic Solutions.. Monatshefte für Mathematik, Tome 125 (1998) no. 4, pp. 343-350. http://geodesic.mathdoc.fr/item/MOMA_1998__125_4_178819/