@article{04085873, title = {Abelian groups in a topos of sheaves: Torsion and essential extensions.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {12}, year = {1989}, pages = {89-98}, doi = {10.1155/S0161171289000128}, zbl = {0664.18001}, language = {en}, url = {http://dml.mathdoc.fr/item/04085873} }
Bhutani, Kiran R. Abelian groups in a topos of sheaves: Torsion and essential extensions.. International Journal of Mathematics and Mathematical Sciences, Tome 12 (1989) pp. 89-98. doi : 10.1155/S0161171289000128. http://gdmltest.u-ga.fr/item/04085873/