1. J.W.J.Williams's original paperon heapsappearedin Communicationsof the ACM in June 1964 and is still fascinatingreading today. Even though it is miniature by today'sstandards(lessthan a pagelong) it is large by the standardsof the time (Floyd's TREESORTalgorithm in the August 1962 Communications was lessthan a quarter of a page!).
2. For a more up-to-dateview of heaps seeTarjan's Data Structures and Network Algorithms published in 1983by the Societyfor Industrial and Applied Mathematics.Chapter 3 is devoted to heaps.This monograph is a fine introduction to the field describedin its title and at only $14.50 you can't afford not to buy it.