publication in the ACM Books series, #25
Editor in Chief: M. Tamer Özsu, University of Waterloo
Area Editor: Bashar Nuseibeh, The Open University
This book was typeset in Arnhem Pro 10/14 and Flama using ZzTEX.
First Edition
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In every block of marble I see a statue as plain as though it stood before me, shaped and perfect in attitude and action. I have only to hew away the rough walls that imprison the lovely apparition to reveal it to the other eyes as mine see it. —Michelangelo
Standing on the shoulders of a giant …
We are liberating the essence from the burden of the whole. —Ivar Jacobson
Contents