@article{MZ_1970__114_171294,
     author = {Dennis Bertholf},
     title = {Isomorphism {Invariants} for {Quotient} {Categories} of {Abelian} {Groups.}},
     journal = {Mathematische Zeitschrift},
     pages = {33--48},
     publisher = {mathdoc},
     volume = {114},
     year = {1970},
     zbl = {0176.30002},
     url = {http://geodesic.mathdoc.fr/item/MZ_1970__114_171294/}
}