@article{10_4153_CMB_1977_006_8,
     author = {Boler, James},
     title = {A {Note} on the {Hopficity} of {Finitely} {Generated} {Free-by-Nilpotent} {Groups}},
     journal = {Canadian mathematical bulletin},
     pages = {33--34},
     year = {1977},
     volume = {20},
     number = {1},
     doi = {10.4153/CMB-1977-006-8},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1977-006-8/}
}