@article{PORMA_1994__51_2_47203,
     author = {Ben Yakoub, L.},
     title = {On a theorem of {P.} {E.} {Schupp.} {(Sur} un th\'eor\`eme de {P.} {E.} {Schupp.)}},
     journal = {Portugaliae mathematica},
     pages = {231--233},
     publisher = {mathdoc},
     volume = {51},
     number = {2},
     year = {1994},
     zbl = {0818.16028},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1994__51_2_47203/}
}