English: Silhouette of the Yak-9P. The World's Fighting Planes (William Green and Gerald Pollinger, McDonald: London 1954) used 55 Crown Copyright silhouettes provided by the Controller of H.M. Stationery. An acknowledgements section on page 6 of the book identifies them by page. This image is one of those and since the publication date is pre-1957 is in the public domain.