[2] S. Burris and H.P. Sankappanavar:
“A Course in Universal Algebra”, Graduate Texts in Mathematics. vol. 78, Springer-Verlag, New York, 1981.
MR 0648287
[4] I. Chajda:
Tolerance trivial algebras and varieties. Acta Sci. Math (Szeged) 46 (1983), 35–40.
MR 0739020 |
Zbl 0534.08001
[5] I. Chajda:
Tolerances in congruence permutable algebras. Czechoslovak Math. J. 38 (1988), 218–225.
MR 0946289 |
Zbl 0678.08004
[6] I. Chajda and J. Rachounek:
Relational characterizations of permutable and $n$-permutable varieties. Czechoslovak Math. J. 33 (1983), 505–508.
MR 0721079
[7] W.H. Cornish:
On Iséki’s BCK-algebras. Lecture Notes in Pure and Applied Mathematics 74 (1982), Marcel Dekker, New York, 101–122.
MR 0647169 |
Zbl 0486.03033
[10] K. Iséki: On ideals of BCK-algebras. Math. Seminar Notes Kobe Univ. 3 (1975), 1–12.
[11] K. Iséki and S. Tanaka:
An introduction to the theory of BCK-algebras. Mathematica Japonica 23 (1978), 1–26.
MR 0500283
[12] J.G. Raftery, I.G. Rosenberg and T. Sturm:
Tolerance relations and BCK-algebras. Mathematica Japonica 36 (1991), 399–410.
MR 1109222
[13] J.G. Raftery and T. Sturm:
On ideal and congruence lattices of BCK-semilattices. Mathematica Japonica 32 (1987), 465–474.
MR 0914750
[14] I.G. Rosenberg and D. Schweigert:
Compatible orderings and tolerances on lattices. Annals of Discrete Mathematics 23 (1984), 119–150.
MR 0779849
[16] A. Wroński: BCK-algebras do not form a variety. Mathematica Japonica 28 (1983), 211–213.
[17] A. Wroński:
Reflections and distensions of BCK-algebras. Mathematica Japonica 28 (1983), 215–225.
MR 0699586
[18] A. Wroński and J.K. Kabziński:
There is no largest variety of BCK-algebras. Mathematica Japonica 29 (1984), 545–549.
MR 0759445