|Amelia Earhart, 1937|
CMG Worldwide represents Amelia Earhart for branding opportunities -- that is, they license Earhart's image, name, or personna to sell a product or service (much like her husband, G.P. Putnam, licensed her name and image for Lucky Strikes). Although CMG states that it "specializes in clearing copyrights, trademarks, and rights of publicity," we couldn't find any evidence that the agency claims or clears copyright on Earhart's literary properties.
Copyright research. In any case, a bit of research may moot any need for permission. Literary works published between 1928 and 1937 are protected for 95 years provided that they were renewed 28 years from first publication. (Less than seven percent of books were renewed). Literary renewals can be searched at Stanford's Copyright Renewal Database. A search for Amelia Earhart turned up one renewal for "The Last Flight," first published in 1937 and renewed in 1964 (see below). So, that work is protected until 2032.