lispdoc - results for tree-equal

(tree-equal x y &key (test #'eql testp) (test-not nil notp))
Function: Return T if X and Y are isomorphic trees with identical leaves.
Example:
(defun same-shape-tree (a b)
  "Are two trees the same except for the leaves?"
  (tree-equal a b :test #'true))
Mentioned in:
CLtL2 - 15.1. Conses
CLtL2 - 6.3. Equality Predicates
HyperSpec - Function TREE-EQUAL
PCL - trees
Successful Lisp - chapter17