Who invented the binary search tree?

So I did a web search for "binary search tree 1962" to see if the BST was invented right around when the AVL tree was invented (the AVL tree was the first balanced BST, and coming up with an AVL tree didn't seem like much of a stretch after the BST was invented). read more

A quick search revealed that the term "binary sequence search tree" was also used to describe the same thing (Sequence search trees: Their analysis using recurrence relations). I found some sources that cited Hibbard as the creator of the delete operation for BSTs (namely Binary Search Trees). read more

Binary search trees keep their keys in sorted order, so that lookup and other operations can use the principle of binary search: when looking for a key in a tree (or a place to insert a new key), they traverse the tree from root to leaf, making comparisons to keys stored in the nodes of the tree and deciding, on the basis of the comparison, to continue searching in the left or right subtrees. read more

From Hibbard's paper "This paper introduces an abstract entity, the binary search tree, and exhibits some of its properties. The properties exhibited are relevant to processes occurring in stored program computers--in particular, to search processes." Wikipedia assigns invention of binary search trees to Windley, Booth, Colin, and Hibbard in 1960. read more