[1] Bandelt H.-J.: Tolerance relations on lattices. Bull. Austral. Math. Soc. 23 (1981), 367-381. MR 0625179 | Zbl 0449.06005

[2] Chajda I.: On the tolerance extension property. Časop. pěst. mat. 103 (1978), 327-332. MR 0512228 | Zbl 0391.06008

[3] Chajda I.: Recent results and trends in tolerances on algebras and varietes. Coiloq. Math. Soc. Janos Bolyai 28: Finite Algebra and Multiple-Valued Logic, North Holland 1981, 69-95. MR 0648608

[4] Chajda I.: The extension property of orderings. Acta Math. Acad. Sci. Hung. 34 (1979), 253-255. MR 0565663 | Zbl 0436.08001

[5] Chajda I., Zelinka B.: Lattices of tolerances. Časop. pěst. mat. 102 (1977), 10-24. MR 0450152 | Zbl 0354.08011

[6] Nieminen J.: Tolerance relations on join-semilattices. Glasnik Mat. (Zagreb) 12 (1977), 143-146. MR 0551488 | Zbl 0376.06011

[7] Schweigert D.: Compatible relations on modular and orthomodular lattices. Pгoc. Amer. Math. Soc. 81 (1981), 462-464. MR 0597663

[8] Zelinka B.: Tolerance relations on semilattices. Comm. Math. Univ. Carolinae 16 (1975), 333-338. MR 0369199 | Zbl 0326.06004