1. P.S. Alexandroff, Untersuchungen über Gestalt und Lage abgeschlossener Mengen beliebiger Dimension, Ann.Math. 30(1929), 101–187.
2. _____, On the homological properties of position of complexes and closed sets (Russian), Izv. Akad. Nauk SSSR Mat. Ser. 6 (1942), 227–282.
3. _____, The main duality theorems for non-closed sets of the n-dimensional space (Russian), Mat.Sb. 21(63), No 2(1947), 161–232.
4. _____, The Combinatorial topology of non-closed sets (Russian), Mat.Sb. 33(75), No 2 (1953), 241–260.
5. _____, Topological duality theorems, I and II (Russian), Trudy Mat.Inst. Steklov, 48 (1955) and 54 (1959).