@article{GDZPPN002347369, title = {On a Problem of Alfsen and Fenstad.}, journal = {Mathematica Scandinavica}, volume = {13}, year = {1963}, pages = {44-46}, zbl = {0129.37605}, url = {http://dml.mathdoc.fr/item/GDZPPN002347369} }
Leader, Solomon. On a Problem of Alfsen and Fenstad.. Mathematica Scandinavica, Tome 13 (1963) pp. 44-46. http://gdmltest.u-ga.fr/item/GDZPPN002347369/