The booklet "Organization Instructions For The Kingdom Publisher" [available for viewing in the 'booklets' section of Strictly Genteel] issued in 1945 and adjusted in 1946 noted on page 26 that the 'Advertising Servant' "should see that sufficient bookmarks are always on hand in the stockroom, so that the Kingdom Hall will be properly advertised through the placement of every bound book".
This is an example of such a bookmark, which was evidently included with every bound book placed with the public.

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