Eric Whitacre's “Sleep” began as a choral composition, setting the text of the Robert Frost poem “Stopping By Woods on a Snowy Evening.” Because of some difficulty securing permissions to use the text, Whitacre came up with the solution of asking poet Charles Anthony Silvestri to set new words to the already-composed music. The piece has been transcribed for several ensembles including cello octet by cellist Jeffrey Zeigler.