Pan Books

Pan Books is a British publishing imprint that was founded in the 1940s and is now part of the British-based Macmillan Publishers, owned by the Georg von Holtzbrinck Publishing Group of Germany.

From the Wikipedia article “Pan Books”, licensed under CC BY-SA 4.0.

An imprint is a brand inside a larger publishing house, often with its own editors and list. Imprints of large groups usually acquire through literary agents; read recent titles to see whether your book fits the list, then target agents who sell to it.