1. Bialynicki-Birula, A.: Remarks on quasi–Boolean algebras. Bull. Acad. Pol. Sci. Cl III 5, 615–619 (1957)
2. Bialynicki-Birula, A., Rasiowa, H.: On the representation of quasi–Boolean algebras. Bull. Acad. Pol. Sci. Cl III 5, 259–261 (1957)
3. Birkhoff, G.: Lattice theory, 3rd edn. American Mathematical Society Colloquium Publication, vol. XXV. American Mathematical Society, Providence (1967); (first edition 1940, second (revisited) edition (1948)
4. Cattaneo, G.: Generalized rough sets (preclusivity fuzzy-intuitionistic BZ lattices). Studia Logica 58, 47–77 (1997)
5. Cattaneo, G.: Abstract approximation spaces for rough theories. In: Polkowski, L., Skowron, A. (eds.) Rough Sets in Knowledge Discovery 1, pp. 59–98. Physica–Verlag, Heidelberg (1998)