@article{CTGDC_1977__18_3_271_0,
     author = {Van Osdol, D. H.},
     title = {Principal homogeneous objects as representable functors},
     journal = {Cahiers de topologie et g\'eom\'etrie diff\'erentielle},
     pages = {271--289},
     publisher = {Dunod \'editeur, publi\'e avec le concours du CNRS},
     volume = {18},
     number = {3},
     year = {1977},
     mrnumber = {506607},
     zbl = {0365.18002},
     language = {en},
     url = {http://www.numdam.org/item/CTGDC_1977__18_3_271_0/}
}