Jan Wielemaker, SWI-Prolog main developer, kindly sent me a paper copy of his PhD thesis. You may grab a PDF version at the following URL:
This is a PhD thesis you don’t want to miss. It describes Jan’s outstanding work developing SWI-Prolog as a top-notch Prolog system and applying logic programming to solve large-scale problems. Hats off to you Jan. Thanks for sharing your hard work with all of us.
P.S. I love the thesis cover.