@article{SM_2008_199_10_a4,
     author = {E. K. Leinartas and M. Passare and A. K. Tsikh},
     title = {Multidimensional versions of {Poincar\'e's} theorem for difference equations},
     journal = {Sbornik. Mathematics},
     pages = {1505--1521},
     publisher = {mathdoc},
     volume = {199},
     number = {10},
     year = {2008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2008_199_10_a4/}
}