@article{1102708978,
author = {Luft, E. and Sjerve, D.},
title = {$3$-manifolds with subgroups ${\bf Z}\oplus {\bf Z}\oplus {\bf Z}$ in their fundamental groups.},
journal = {Pacific J. Math.},
volume = {115},
number = {2},
year = {1984},
pages = { 191-205},
language = {en},
url = {http://dml.mathdoc.fr/item/1102708978}
}
Luft, E.; Sjerve, D. $3$-manifolds with subgroups ${\bf Z}\oplus {\bf Z}\oplus {\bf Z}$ in their fundamental groups.. Pacific J. Math., Tome 115 (1984) no. 2, pp. 191-205. http://gdmltest.u-ga.fr/item/1102708978/