@article{JRAM_1995__461_153708,
     author = {Joseph H. Silverman and Patrick Morton},
     title = {Periodic points, multiplicities, and dynamical units.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {81--122},
     publisher = {mathdoc},
     volume = {461},
     year = {1995},
     zbl = {0813.11059},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1995__461_153708/}
}