1. Quelques remarques concernant les opérations sur les fonctions semi-continues dans les espaces topologiques;Engelking, R.;Bull. Acad. Polon. Sci. S\'{e}r. Sci. Math. Astronom. Phys.,1963
2. Closed and image-closed relations;Franklin, S. P.;Pacific J. Math.,1966
3. A decomposition of continuity in topological spaces;Levine, Norman;Amer. Math. Monthly,1961
4. Academic Press Textbooks in Mathematics;Pervin, William J.,1964
5. Almost and weak continuity for multifunctions;Smithson, R. E.;Bull. Calcutta Math. Soc.,1978