The field was originally developed by Christopher Strachey and Dana Scott.
Denotational semantics generally makes use of the techniques of functional programming to describe computer languages, architectures and programs. The mathematics of denotational semantics is usually now formulated within domain theory.
The classic work on the subject is:
Joseph E. Stoy. Denotational Semantics: The Scott-Strachey Approach to Programming Language Semantics. MIT Press, Cambridge, Massachusetts, 1977.