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From records in the U.S. Library of Congress [ref name=LCC] and WorldCat (via P.L. Travers at WorldCat),  I infer that it was published first in the United States, 1943 rather than 1944. (Alternatively, U.S. libraries have used copyright rather than publication year.) The records give much different page counts, 219 UK and 239 US; both with credit to both Mary Shepard and Agnes Sims as illustrators. The Opie Collection of Children's Literature record for its microfiche of the first edition is most informative, so I linked that one in the infobox, OCLC  64447512.

If published 1943 US and 1944 UK, I wonder whether British publication was delayed by some wartime shortage of paper or another material. -- P64 ( talk) 19:10, 22 May 2015 (UTC) reply