@article{05191454,
title = {Closedness properties of internal relations. IV: Expressing additivity of a category via subtractivity.},
journal = {Journal of Homotopy and Related Structures},
volume = {1},
year = {2006},
pages = {219-227},
zbl = {1124.18003},
language = {en},
url = {http://dml.mathdoc.fr/item/05191454}
}
Janelidze, Zurab. Closedness properties of internal relations. IV: Expressing additivity of a category via subtractivity.. Journal of Homotopy and Related Structures, Tome 1 (2006) pp. 219-227. http://gdmltest.u-ga.fr/item/05191454/