treet

from The Free On-line Dictionary of Computing (8 July 2008)

TREET

   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].