1. G. Birkhoff,Lattice theory (New York, 1948).
2. G. Birkhoff andO. Frink, Representations of lattice by sets,Trans. Amer. Math. Soc.,64 (1948), pp. 299–316.
3. I. R. Büchi, Representation of complete lattices by sets,Porth. Math.,11 (1952), pp. 151–163.
4. P. Crawley, Lattices whose congruences form a Boolean algebra,Pacific J. of Math.,10 (1960), pp. 787–798.
5. G. Grätzer andE. T. Schmidt, Two notes on lattice congruences,Annales Univ. Sci. Budapest, Sectio Math.,1 (1958), pp. 83–87.