@article{1077311346, author = {Lind, D. A.}, title = {A counterexample to a conjecture of Hopf}, journal = {Duke Math. J.}, volume = {42}, number = {1}, year = {1975}, pages = { 755-757}, language = {en}, url = {http://dml.mathdoc.fr/item/1077311346} }
Lind, D. A. A counterexample to a conjecture of Hopf. Duke Math. J., Tome 42 (1975) no. 1, pp. 755-757. http://gdmltest.u-ga.fr/item/1077311346/