@article{GDZPPN00203753X,
title = {Subadditive functions on modules and subgroups of abelian groups.},
journal = {Aequationes mathematicae},
volume = {38},
year = {1989},
pages = {15-37},
zbl = {0668.39004},
url = {http://dml.mathdoc.fr/item/GDZPPN00203753X}
}
Pelling, M.J. Subadditive functions on modules and subgroups of abelian groups.. Aequationes mathematicae, Tome 38 (1989) pp. 15-37. http://gdmltest.u-ga.fr/item/GDZPPN00203753X/