The 21st edition contains more than 60,000 terms and 1,000 images.
Each edition will contain at least 64 pages, half of them in color.
A second improved edition in 1575 contained seven new stories.
The second edition of the set already contained 130 authors and 517 individual works.
Some editions of the text contain 53 problems, others 56.
Second edition now contains more puzzles, each at a lower price.
The standard edition contains the full game, which was released October 27, 2006.
The second edition was published in 2008 and contains 5000 entries.
Later editions of this work (2000 and 20007) contain additional information.
Because his original books are rather short, these editions may contain 15 or more in each volume.
