@article{GDZPPN002354098, title = {Ward's Staut-Clausen problem.}, journal = {Mathematica Scandinavica}, volume = {38}, year = {1976}, pages = {239-250}, zbl = {0347.10010}, url = {http://dml.mathdoc.fr/item/GDZPPN002354098} }
Horadam, A.F.; Shannon, A.G. Ward's Staut-Clausen problem.. Mathematica Scandinavica, Tome 38 (1976) pp. 239-250. http://gdmltest.u-ga.fr/item/GDZPPN002354098/