@article{PORMA_1975__34_1_115247,
     author = {Propes, R.E.},
     title = {Some notes on upper radical classes},
     journal = {Portugaliae mathematica},
     pages = {21--23},
     publisher = {mathdoc},
     volume = {34},
     number = {1},
     year = {1975},
     mrnumber = {0387336},
     zbl = {0315.16006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1975__34_1_115247/}
}