I have been working with South Florida books for many years and often thought of a way to evaluate which books were the most important.  Of course many books have bibliographies. As a matter of fact, I have become a connoisseur of bibliographies.  So, I made a file combining the bibliographies of many books and arranged the books mentioned in the order of most cited. This is exactly the technique Google uses. Maybe they took it from me?  The result is: a list of the books most often cited in bibliographies.

This list favors books relating to history, biography, and the natural sciences. There are no novels here or cookbooks or poetry or true crime or gardening books.  The bookshelf pictured here holds fifteen books.   In the time since I took the photograph I have revised the list and they no longer quite match.