@article{MS2_1983__52_166827, author = {J.H.E. Cohn}, title = {Squares in arithmetical progressions {II.}}, journal = {Mathematica Scandinavica}, pages = {20--23}, publisher = {mathdoc}, volume = {52}, year = {1983}, zbl = {0511.10014}, url = {http://geodesic.mathdoc.fr/item/MS2_1983__52_166827/} }