This is by Burt Bacharach (music) and Hal David (lyric). It appeared in the (1969?) movie "Butch Cassady and the Sundance Kid" starring Paul Newman and Robert Redford. B. J. Thomas sang it in the movie soundtrack and also released a single (a different recording), which became a #1 hit. A sheet music piano and voice arrangement (with guitar chord symbols) was published at the time the single was released. Piano and voice arrangements also appeared in a folio of songs nominated for Academy Awards that year (whatever year it was) and in a folio of Burt Bacharach and Hal David songs. If your local music store can't find a copy for you, your local public library might very well have a copy of the latter folio. A good university music library is almost sure to.

I'm not sure why you've posted your question in the "Musicals" forum, by the way, but it so happens that Bacharach and David did write one hit Broadway musical, "Promises, Promises". Dionne Warwick had hits with the title song and another song from the musical, "I'll Never Fall in Love Again".