Inside back cover. The use of credit lines in publications prepared for distribution under the penalty mailing privilege is permissible. The use of credit lines, as outlined in paragraph 3, are permissible but not a requirement. Credit may also be given to photographers, illustrators, etc., who make a significant contribution to a publication. Credit lines are permissible for copyrighted and uncopyrighted illustrations, charts, photographs, etc.
Credit lines are also permissible for material provided by governmental sources.
Name of authors and editors may be placed on the title page or listed with other credits. Name of photographers, illustrators, etc., may be placed inside front or back cover or the back cover if all photographs or illustrations, etc., come from the same person. However, if several photographers or illustrators are involved, credit lines may appear on the page with the individual contribution or in the above positions, but not both. Credit for donated or loaned material from other sources may also be placed inside the front or back cover. The foregoing would also apply to the use of courtesy credit statements for text quoted from copyrighted and uncopyrighted publications.