@article{BUMI_2007_8_10B_1_a2,
     author = {Anderson, Daniel D. and Zafrullah, Muhammad},
     title = {The {Schreier} {Property} and {Gauss'} {Lemma}},
     journal = {Bollettino della Unione matematica italiana},
     pages = {43--62},
     publisher = {mathdoc},
     volume = {Ser. 8, 10B},
     number = {1},
     year = {2007},
     zbl = {1129.13025},
     mrnumber = {2310957},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/BUMI_2007_8_10B_1_a2/}
}