"These stories were first published in Mr Pink-Whistle's party and Mr Pink-Whistle interferes by George Newnes, 1950 and 1955"--t.p. verso.
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Mr Pink-Whistle has some fun by Enid Blyton. ISBN 0747543453. Published by Bloomsbury Children's Books in 1999. Publication and catalogue information, links to buy online and reader comments.
