@article{1103044613, author = {Lehmer, Emma}, title = {On the number of solutions of $u^k+D\equiv w^2(\mod p)$.}, journal = {Pacific J. Math.}, volume = {5}, number = {4}, year = {1955}, pages = { 103-118}, language = {en}, url = {http://dml.mathdoc.fr/item/1103044613} }
Lehmer, Emma. On the number of solutions of $u^k+D\equiv w^2(\mod p)$.. Pacific J. Math., Tome 5 (1955) no. 4, pp. 103-118. http://gdmltest.u-ga.fr/item/1103044613/