[1] Grzegorz Bancerek. Cardinal numbers. *Formalized Mathematics*, 1(**2**):377-382, 1990.

[2] Grzegorz Bancerek. The fundamental properties of natural numbers. *Formalized Mathematics*, 1(**1**):41-46, 1990.

[3] Grzegorz Bancerek. The ordinal numbers. *Formalized Mathematics*, 1(**1**):91-96, 1990.

[4] Grzegorz Bancerek. Tarski’s classes and ranks. *Formalized Mathematics*, 1(**3**):563-567, 1990.

[5] Grzegorz Bancerek. Mizar analysis of algorithms: Preliminaries. *Formalized Mathematics*, 15(**3**):87-110, 2007, doi:10.2478/v10037-007-0011-x. [Crossref]

[6] Grzegorz Bancerek and Krzysztof Hryniewiecki. Segments of natural numbers and finite sequences. *Formalized Mathematics*, 1(**1**):107-114, 1990.

[7] Czesław Bylinski. Functions and their basic properties. *Formalized Mathematics*, 1(**1**):55-65, 1990.

[8] Czesław Bylinski. Some basic properties of sets. *Formalized Mathematics*, 1(**1**):47-53, 1990.

[9] Agata Darmochwał. Finite sets. *Formalized Mathematics*, 1(**1**):165-167, 1990.

[10] Frank Harary. *Graph theory*. Addison-Wesley, 1969.

[11] Rafał Kwiatek. Factorial and Newton coefficients. *Formalized Mathematics*, 1(**5**):887-890, 1990.

[12] J. Mycielski. Sur le coloriage des graphes. *Colloquium Mathematicum*, 3:161-162, 1955.

[13] Beata Padlewska. Families of sets. *Formalized Mathematics*, 1(**1**):147-152, 1990.

[14] Konrad Raczkowski and Paweł Sadowski. Equivalence relations and classes of abstraction. *Formalized Mathematics*, 1(**3**):441-444, 1990.

[15] Piotr Rudnicki and Lorna Stewart. The Mycielskian of a graph. *Formalized Mathematics*, 19(**1**):27-34, 2011, doi: 10.2478/v10037-011-0005-6. [Crossref]

[16] Andrzej Trybulec. Enumerated sets. *Formalized Mathematics*, 1(**1**):25-34, 1990.

[17] Andrzej Trybulec. Many sorted sets. *Formalized Mathematics*, 4(**1**):15-22, 1993.

[18] Andrzej Trybulec and Agata Darmochwał. Boolean domains. *Formalized Mathematics*, 1(**1**):187-190, 1990.

[19] Zinaida Trybulec. Properties of subsets. *Formalized Mathematics*, 1(**1**):67-71, 1990.

[20] Oswald Veblen. *Analysis Situs*, volume V. AMS Colloquium Publications, 1931

This work has been partially supported by the NSERC grant OGP 9207

Published Online: 2013-02-02Published in Print: 2012-12-01Citation Information:Formalized Mathematics. Volume 20, Issue 2, Pages 161–174, ISSN (Online) 1898-9934, ISSN (Print) 1426-2630, DOI: https://doi.org/10.2478/v10037-012-0019-8, February 2013This content is open access.