E.C. Haines, 1964. An experimental variant of LISP1.5, implemented on the STRETCH computer. Basic structure was a trinary tree.

["The TREET Time-Sharing System", H.A. Bayard et al, Proc 2nd Symp Symb and Alg Manip, ACM (Mar 1971)].

[Sammet 1969, pp.457-461].

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tree-killertree shakingTREETTREETRANTree Transformation Language

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