@article{10_21136_CPM_1976_117918,
     author = {Mehri, Bahman},
     title = {On the existence of periodic boundary conditions for nonlinear second order differential equations},
     journal = {\v{C}asopis pro p\v{e}stov\'an{\'\i} matematiky},
     pages = {256--262},
     publisher = {mathdoc},
     volume = {101},
     number = {3},
     year = {1976},
     doi = {10.21136/CPM.1976.117918},
     mrnumber = {0481239},
     zbl = {0341.34028},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CPM.1976.117918/}
}