@article{1093958157,
author = {Soboci\'nski, Boles\l aw},
title = {A note on certain set-theoretical formulas.},
journal = {Notre Dame J. Formal Logic},
volume = {6},
number = {1},
year = {1965},
pages = { 157-160},
language = {en},
url = {http://dml.mathdoc.fr/item/1093958157}
}
Sobociński, Bolesław. A note on certain set-theoretical formulas.. Notre Dame J. Formal Logic, Tome 6 (1965) no. 1, pp. 157-160. http://gdmltest.u-ga.fr/item/1093958157/