@article{1183485275,
author = {Walsh, J. L.},
title = {A generalization of normal congruences of circles},
journal = {Bull. Amer. Math. Soc.},
volume = {28},
number = {9},
year = {1922},
pages = { 456-462},
language = {en},
url = {http://dml.mathdoc.fr/item/1183485275}
}
Walsh, J. L. A generalization of normal congruences of circles. Bull. Amer. Math. Soc., Tome 28 (1922) no. 9, pp. 456-462. http://gdmltest.u-ga.fr/item/1183485275/