Rick is in a short story.

[Mya]

Other Worlds is a new sci-fi short stories book. which - if you haven't guessed by the title- Rick Riordan is in. His short story is called (drum roll) Percy Jackson and the Singer of Apollo. Also Other Worlds will be published August 29th 2013. http://www.goodreads.com/book/show/18... Have a look yourself.