- (Wikipedia, 2019) ⇒ https://en.wikipedia.org/wiki/Order_theory Retrieved:2019-4-25.
- Order theory is a branch of mathematics which investigates the intuitive notion of order using binary relations. It provides a formal framework for describing statements such as "this is less than that" or "this precedes that". This article introduces the field and provides basic definitions. A list of order-theoretic terms can be found in the order theory glossary.
- (Dean, 2015) ⇒ Mark Dean (2015). "Order Theory". In: Lecture Notes for Fall 2015 PhD Class in Decision Theory - Brown University
- QUOTE: We are going to begin the class with some mathematical preliminaries. First, we will review some results from order theory - the branch of maths that deals with binary relations. We are interested in some of the results that order theory has to offer because many of the representation theorems that we will be looking at involve preference relations of some form or another, and preference relations are just one particular type of binary relation.