Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{AM2_1971__6_136170, author = {WALTER WUNDERLICH}, title = {Kurven mit isoptischen {Kreis}}, journal = {Aequationes mathematicae}, pages = {71--81}, publisher = {mathdoc}, volume = {6}, year = {1971}, zbl = {0215.50103}, url = {http://geodesic.mathdoc.fr/item/AM2_1971__6_136170/} }
WALTER WUNDERLICH. Kurven mit isoptischen Kreis. Aequationes mathematicae, Tome 6 (1971), pp. 71-81. http://geodesic.mathdoc.fr/item/AM2_1971__6_136170/