John F. Kennedy Stamp
According to a entry on Wikipedia, "This was a challenging deadline, requiring the stamp to be designed, approved by the late President's widow, Jacqueline Kennedy, and printed in large quantities in just a few months (it was estimated that two million first day covers would need to be available)."
The entry goes on to say, "The first proposals of the Bureau of Engraving and Printing were turned down in December 1963 and in early January 1964. The decision was then made to call in the Loewy/Snaith design firm. Raymond Loewy accepted the stamp design project more for the firm's reputation than for money; the firm earned $500 for this project, a small and symbolic amount considering the amount of work involved.
"Over the next three months, Loewy's designers worked on the project. To maintain secrecy, Loewy locked the papers and projects in his safe every day, putting his thumb's fingerprint on them.Finally, Mrs. Kennedy was consulted, choosing both the design proposal and its color, a blue-gray similar to that used in the interior of Air Force One."
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