A & C Black

A & C Black is a British book publishing company, owned since 2000 by Bloomsbury Publishing. The company is noted for publishing Who's Who since 1849 and the Encyclopædia Britannica between 1827 and 1903. It offers a wide variety of books in fiction and nonfiction, and has published popular travel guides, novels, and science books.

From the Wikipedia article “A & C Black”, 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.