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@article{JMPA_1930_9_9__383_0, author = {Weatherburn, C. E.}, title = {On the {Lines} of {Equidistance} of a {Family} of {Surfaces}}, journal = {Journal de Math\'ematiques Pures et Appliqu\'ees}, pages = {383--390}, publisher = {Gauthier-Villars}, volume = {Ser. 9, 9}, year = {1930}, language = {en}, url = {http://geodesic.mathdoc.fr/item/JMPA_1930_9_9__383_0/} }
Weatherburn, C. E. On the Lines of Equidistance of a Family of Surfaces. Journal de Mathématiques Pures et Appliquées, Série 9, Tome 9 (1930), pp. 383-390. http://geodesic.mathdoc.fr/item/JMPA_1930_9_9__383_0/