## The dimension of a comparability graph

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- by W. T. Trotter, John I. Moore and David P. Sumner PDF
- Proc. Amer. Math. Soc.
**60**(1976), 35-38 Request permission

## Abstract:

Dushnik and Miller defined the dimension of a partial order*P*as the minimum number of linear orders whose intersection is

*P*. Ken Bogart asked if the dimension of a partial order is an invariant of the associated comparability graph. In this paper we answer Bogart’s question in the affirmative. The proof involves a characterization of the class of comparability graphs defined by Aigner and Prins as uniquely partially orderable graphs. Our characterization of uniquely partially orderable graphs is another instance of the frequently encountered phenomenon where the obvious necessary condition is also sufficient.

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## Additional Information

- © Copyright 1976 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**60**(1976), 35-38 - MSC: Primary 06A10
- DOI: https://doi.org/10.1090/S0002-9939-1976-0417001-6
- MathSciNet review: 0417001