Trinity College Dublin
History of Mathematics: Bonaventura Cavalieri (1598 1647)
A biography of Cavalieri that includes information on his principle or "indivisibles." From a 1904 text by W. W. Rouse Ball.
University of St. Andrews (UK)
University of St. Andrews: Bonaventura Cavalieri
This site from the University of St. Andrews, gives factual biological information on Cavalieri. Links are provided at the end of the site for more information.