@article{1093887645,
author = {Sobel, Jordan Howard},
title = {Alternative notations for Principia Mathematica description theory: possible modifications.},
journal = {Notre Dame J. Formal Logic},
volume = {17},
number = {1},
year = {1976},
pages = { 476-478},
language = {en},
url = {http://dml.mathdoc.fr/item/1093887645}
}
Sobel, Jordan Howard. Alternative notations for Principia Mathematica description theory: possible modifications.. Notre Dame J. Formal Logic, Tome 17 (1976) no. 1, pp. 476-478. http://gdmltest.u-ga.fr/item/1093887645/