@article{EJDE_2002__2002__a173,
     author = {Raffoul, Youssef N.},
     title = {Positive periodic solutions of nonlinear functional difference equations},
     journal = {Electronic Journal of Differential Equations},
     publisher = {mathdoc},
     volume = {2002},
     year = {2002},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2002__2002__a173/}
}