@article{1181071746, author = {Dofs, Erik}, title = {Unsolvable Cases of $P^3+Q^3+cR^3=dPQR$}, journal = {Rocky Mountain J. Math.}, volume = {28}, number = {4}, year = {1998}, pages = { 927-938}, language = {en}, url = {http://dml.mathdoc.fr/item/1181071746} }
Dofs, Erik. Unsolvable Cases of $P^3+Q^3+cR^3=dPQR$. Rocky Mountain J. Math., Tome 28 (1998) no. 4, pp. 927-938. http://gdmltest.u-ga.fr/item/1181071746/