The author of "Number 9 Dream" (David Stephen Mitchell (born 12 January 1969) is an English novelist.) has never written "Back story" and "What You Do Not Know You Want" which are creation of other persons. Please, separate properly!
He has never written "Back story" actually. "What You Do Not Know You Want" is his short story from McSweeney's Enchanted Chamber of Astonishing Stories, Vintage Books (Random House), 2004
