"There are over one thousand entries, comprising 403 titles of specialist books and pamphlets, 493 subsequent editions and variants, and 158 patents. Most of the subject documents are in English, but the French, German, Italian, Swedish, Afrikaans, Chinese and Japanese languages are also represented."--Jacket.

Early volumes consisted of rules with a separate publication for text. Later volumes consist of text and rules, (at first, the official rules, later the "read-easy" rules.) Vols. for 1976-78 do not include rules.