Definition
- A topological space (X,τ) is called pre-T_0 iff to each pair of distinct points x, y in X, there exists a pre-open? set containing one of the points but not the other.
Reference
- Athisaya Ponmani, S.; Lellis Thivagar, M., Another form of separation axioms. , (English) [J] Methods Funct. Anal. Topol. 13, No. 4, 380-385 (2007).