1. On the characterization of the lattice of topologies;Bagley, R. W.;J. London Math. Soc.,1955
2. Über den Ultrafilterraum;Banaschewski, Bernhard;Math. Nachr.,1955
3. M. P. Berri, Lattice complements of certain topologies, Abstract 65T-94 Notices Amer. Math. Soc. 12 (1965), 227.
4. The complement of a topology for some topological groups;Berri, M. P.;Fund. Math.,1966
5. American Mathematical Society Colloquium Publications, Vol. 25;Birkhoff, Garrett,1948