First printing in October 2000, second printing in April 2001, third in May 2002 and fourth in January 2006 (both softcover). The ISBN numbers are 1-85233-268-9 and 1-85233-611-0.

Courtesy to Springer-Verlag, you may now read the first edition of the book free of charge.

Note that this is a corrected version of the 1st edition of the book and, among other things, can be used to clarify some places of the book where a serious misprint or mistake occurs.

Several conjectures from the book has been solved. Here is information on the solved conjectures.

Mathematics Subjects Classifications: 05C20, 05C38, 05C40, 05C45, 05C70, 05C85, 05C90, 05C99, 68R10, 68Q25, 68W05, 68W40 90B06, 90B70, 90C35, 94C15

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