@article{JRAM_1987__380_152959,
     author = {Denis Sjerve and Henry Glover},
     title = {The genus of {PSl2} (q).},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {59--86},
     publisher = {mathdoc},
     volume = {380},
     year = {1987},
     zbl = {0613.57019},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1987__380_152959/}
}