1. Garrett Birkhoff, Lattice Theory, third edition, AMS Colloq. Publications, v. XXV, 1967. MR 37 #2638.
2. Paul Halmos, Naive Set Theory, Van Nostrand University Series in Undergraduate Mathematics, 1960; Springer Undergraduate Texts in Mathematics, 1974. MR 22 #5575, MR 56 #11794.
3. J. Donald Monk, Introduction to Set Theory, McGraw-Hill, 1969. MR 44 #3877.
4. Robert L. Vaught, Set Theory, an Introduction, Birkhäuser, 1985; second edition 1995. MR 95k :03001.
5. Thomas W. Hungerford, Algebra, Springer GTM, v. 73, 1974. MR 50 #6693.