Point-Set Topology by Romyar Sharifi / Chapter 1: Topological spaces

Online text: www.math.ucla.edu/~sharifi/notes/topology-ch01.html

Cited passages: Definition 1.1.9: finite complement topology; Definition 1.5.5, Proposition 1.5.11 and Proposition 1.6.20: neighbourhood convergence, uniqueness and the metric formulation; Example 1.5.10 and Proposition 1.5.11: closed points, overlapping neighbourhoods, non-repeating sequences and uniqueness in Hausdorff spaces.