@article{BSL6_4_Epstein,
author = {George EPSTEIN},
title = {On the Equivalence of the Meskhi and Cignoli Conditions for $P$-Algebras with Involution, with Application to Łukasiewicz 3 and 4-Valued Logics},
journal = {Bulletin of the Section of Logic},
volume = {6},
number = {4},
year = {1977},
pages = {156--160}
}