S. Baron: Note on epi in T0. Can. Math. Bull. 11 (1968), 503-504.

20102 W. Burgess: The meaning of mono and epi in some familiar
categories. Can. Math. Bull. 8/6 (1965), 759-769.

G. Castellini: Categorical closure operators. Birkhäuser 2003, 300p. Eur 95.

21158 Horst Herrlich: Topologische Reflexionen und Coreflexionen.
Springer LN Math. 78 (1968), 170p. Eur 20.

27315 Philip Hirschhorn: The Quillen model category of topological spaces.
Internet 2017, 22p.

27095 Hans-Joachim Kowalsky: Kategorien topologischer Räume.
Math. Zeitschr. 77 (1961), 249-272.

Gerhard Preuss: Theory of topological structures - an approach to categorical 
topology. Reidel 1987, 300p. Dfl. 148.


29419 Dana Schlomiuk: An elementary theory of the category of topological spaces.
Trans. AMS 149 (1970), 259-278.

20101 Joachim Schröder: Epi und extremer Mono in T2a.
Archiv Math. 25 (1974), 561-565.