In 1945 Penguin proprietor, Allen Lane established an American branch called Penguin Books, Inc (PBI). Lane hired Kurt Enoch and Victor Weybright to run PBI in New York. Three years later Enoch and Weybright founded New American Library (NAL) and introduced Signet and Mentor as leading imprints http://www.penguinputnam.com/static/html/aboutus/adult/nal.html (Sighted 2/12/04).
Signet was one of the first companies to print paperback originals (pbos). Late in the 1950s, they licensed Carter Brown Mystery Series in a joint publishing agreement with Sydney publisher Horwitz. Another Horwitz author Shane Douglas contributed two books Air Surgeon, Mercy Heroes. Signet also published Manning Clark's History of Australia (which was edited by the same editor of the Carter Brown series, Brad Cumings), Ray Lawler's Summer of the Seventeenth Doll and Nevil Shute's On the Beach (for which they paid a US$10,000 advance for reprint rights in 1957).
Mentor reproduced cheap 'classics' and non-fiction mainly for the college market.