@article{CMUC_1965_6_1_a12,
     author = {Vop\v{e}nka, Petr},
     title = {Concerning a proof of $\aleph_{\alpha+1}\leq 2^{\aleph_\alpha}$ without axiom of choice},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {111--113},
     year = {1965},
     volume = {6},
     number = {1},
     mrnumber = {0174484},
     zbl = {0199.01701},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1965_6_1_a12/}
}