@article{IM_1992__108_2_143996,
     author = {Eriko Hironaka},
     title = {Polynomial periodicity for {Betti} numbers of covering surfaces.},
     journal = {Inventiones mathematicae},
     pages = {289--322},
     year = {1992},
     volume = {108},
     number = {2},
     zbl = {0776.14002},
     url = {http://geodesic.mathdoc.fr/item/IM_1992__108_2_143996/}
}