[1] R. BALBES, A. HORN: Infective and projective Heyting algebras. Trans. Amer. Math. Soc. 148 (1970), 549-559. MR 0256952

[2] P. COHN: Universal Algebra. Harper and Row, 1965. MR 0175948 | Zbl 0141.01002

[3] P. DUBREIL: Endomorphismes. Séminaire Dubreil-Pisot, Paris, 1964/65, No 23.

[4] G. GRÄTZER: Universal Algebra. Van Nostrand, 1968. MR 0248066

[5] H. RASIOWA, R. SIKORSKI: The mathematics of metamathematios. Monogr. Mat., t. 41, PWN, Warsaw, 1963.

[6] D. SMITH: Meet-irreducible elements in implicative lattices. Proc. Amer. Math. Soc. 34 (1972), 57-62. MR 0291035 | Zbl 0259.06008

[7l J. VARLET: Contribution à l'étude des treillis pseudocomplémentés et des treillis de Stone. Memoires Soc. Roy. Sc. Liège,t. 8, fasc. 4 (1962), 1-71. MR 0164909

[8] J. VARLET: Relative annihilators in semilattices. to appear in Bull. Austral. Math. Soc. MR 0382091 | Zbl 0258.06009