*Definition [#g5700fe4]
-A topological space (X, τ) is said to be λ-T_0 if for x, y ∈ X such that &ref(http://www.eaflux.com/imgtex/imgtex.fcgi?%5bres=100%5d%7b%5c%5b%20x%5cneq%20y%20%5c%5d%7d%25.png);  there exists an [[λ-open set>λ-open]] containing x but not y or a λ-open set containing y but not x .

*Property [#x5f2fd59]
-λ-T_0 ⇔ [[λ-D_0]].

*Reference [#o6c703b2]
-Caldas Miguel, Jafari Saeid, Navalagi Govindappa, ''More on λ-closed sets in topological spaces.'',Rev. Colombiana Mat. 41 (2007), no. 2, 355-369.