Prior to that, King Features did publish the copyright books, King Features Illustrated Weekly and King Features Weekly, starting around 1938. These books originally took proof pages made from comic strips (and other feature and editorial non-comic material) intended for newspaper syndication, made reduced copies of the pages, bound them together under a title, and sent them to the Library of Congress to secure copyright on the material. Occasionally these titles surface publicly indicating that they might be offered for sale of subscription periodically.
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