Classical lambda calculus in modern dress
  Recent developments in the categorical foundations of universal algebra have given fresh impetus to an understanding of the lambda calculus coming from categorical logic: an interpretation is a semi-closed algebraic theory. Scott's representation theorem is then completely natural and leads to precise theorems showing the essential equivalence with more familiar notions. Simple abstract proofs of fundamental results in the semantics of the lambda calculus are given. 
Martin Hyland
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