@article{PIM_1991_N_S_49_63_a2,
     author = {Ivan Gutman},
     title = {A {Property} {Of} {The} {Number} {Of} {Perfect} {Matchings} {Of} {A} {Graph}},
     journal = {Publications de l'Institut Math\'ematique},
     pages = {17 },
     year = {1991},
     volume = {_N_S_49},
     number = {63},
     url = {http://geodesic.mathdoc.fr/item/PIM_1991_N_S_49_63_a2/}
}