@article{BSL9_3_Palasinski,
author = {Marek PA{\L}ASI{\'N}SKI},
title = {On Ideals in Directed Commutative $BCK$-Algebras},
journal = {Bulletin of the Section of Logic},
volume = {9},
number = {3},
year = {1980},
pages = {145--149}
}