@article{02217492, title = {Periodic boundary value problems for }, journal = {Journal of Applied Mathematics}, volume = {2005}, year = {2005}, pages = {1-21}, doi = {10.1155/JAM.2005.1}, zbl = {1088.34013}, language = {en}, url = {http://dml.mathdoc.fr/item/02217492} }
Liu, Yuji; Ge, Weigao. Periodic boundary value problems for . Journal of Applied Mathematics, Tome 2005 (2005) pp. 1-21. doi : 10.1155/JAM.2005.1. http://gdmltest.u-ga.fr/item/02217492/