@article{PIM_2000_N_S_68_82_a4,
     author = {Seymour Lipschutz and Wujie Shi},
     title = {Note on a question of {Reinhold} {Baer} on pregroups},
     journal = {Publications de l'Institut Math\'ematique},
     pages = {53 },
     publisher = {mathdoc},
     volume = {_N_S_68},
     number = {82},
     year = {2000},
     zbl = {1011.20002},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PIM_2000_N_S_68_82_a4/}
}