@article{PORMA_1991__48_1_115736,
     author = {Craveiro de Carvalho, F.J. and Robertson, S.A.},
     title = {A correction to },
     journal = {Portugaliae mathematica},
     pages = {9--9},
     publisher = {mathdoc},
     volume = {48},
     number = {1},
     year = {1991},
     mrnumber = {1107254},
     zbl = {0721.53053},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1991__48_1_115736/}
}