@article{GDZPPN002310813, title = {Which Abelian Surfaces are Products of Elliptic Curves ?}, journal = {Mathematische Annalen}, volume = {217}, year = {1975}, pages = {35-48}, zbl = {0283.14007}, url = {http://dml.mathdoc.fr/item/GDZPPN002310813} }
Oort, Frans. Which Abelian Surfaces are Products of Elliptic Curves ?. Mathematische Annalen, Tome 217 (1975) pp. 35-48. http://gdmltest.u-ga.fr/item/GDZPPN002310813/