@article{JRAM_1977__292_151883,
     author = {Wells Johnson},
     title = {On the nonvanishing of {Fermat} quotients (mod p).},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {196--200},
     publisher = {mathdoc},
     volume = {292},
     year = {1977},
     zbl = {0347.10001},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1977__292_151883/}
}