@article{CMH_1974__49_139596,
     author = {Peter Lappan},
     title = {A {Criterion} for a {Meromorphic} {Function} to be {Normal}},
     journal = {Commentarii mathematici Helvetici},
     pages = {492--495},
     publisher = {mathdoc},
     volume = {49},
     year = {1974},
     zbl = {0292.30029},
     url = {http://geodesic.mathdoc.fr/item/CMH_1974__49_139596/}
}