# Door space

From Encyclopedia of Mathematics

2010 Mathematics Subject Classification: *Primary:* 54F99 [MSN][ZBL]

A topological space in which every subset is either open or closed.

Door spaces are examples of submaximal spaces.

#### References

- McCartan, S.D.
*Door spaces are identifiable*Proc. R. Ir. Acad., Sect. A**87**(1987) 13-16 Zbl 0646.54028

**How to Cite This Entry:**

Door space.

*Encyclopedia of Mathematics.*URL: http://encyclopediaofmath.org/index.php?title=Door_space&oldid=39776

This article was adapted from an original article by A.A. Mal'tsev (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article