Pseudonym the attempt was not entirely successful – and the two are still sometimes confused by booksellers. A pen name may be used specifically to hide the identity of the author, as in the case of exposé books about espionage or crime, or explicit erotic fiction. Some prolific authors adopt a pseudonym to disguise the extent of their published output, e.g. Stephen King writing as Richard Bachman. Co-authors may choose to publish under a collective pseudonym, e.g., P. J. Tracy and Perri O'Shaughnessy. Frederic Dannay and Manfred Lee used the name Ellery Queen as both a pen name for their collaborative
Pen name sometimes choose to use initials, such as K. A. Applegate, C. J. Cherryh, P. N. Elrod, D. C. Fontana, S. E. Hinton, G. A. Riplinger, J. D. Robb, and J. K. Rowling. Alternatively, they may use a unisex pen name, such as Robin Hobb (the second pen name of novelist Margaret Astrid Lindholm Ogden). A collective name, also known as a house name, is sometimes used with series fiction published under one pen name even though more than one author may have contributed to the series. In some cases the first books in the series were written by one writer,