© Copyright Avi Sion, 1990 – 2005 .
Protected by international and Pan-American copyright conventions.
No part of this book may be reproduced in any manner whatsoever, or stored in a retrieval system or transmitted, without express permission of the Author-publisher, except in case of brief quotations with due acknowledgement.
Published 2003, by The Logician, c/o Avi Sion in Geneva, Switzerland.
(Expanded edition, 2005. Small revisions, 2009.)