sentences:  There is a growing view among scholars that the distinction made by experts such as Alan Lomax between "deep" blues singers and "songsters" is an artificial one, and that in fact most of the leading archetypal blues artists, including Robert Johnson and Muddy Waters, performed a wide variety of music in public, but recorded only that proportion of their material which was seen by their producers as original or innovative.In The Salvation Army the term "songster" refers to a soldier (member) who is commissioned to sing in a Salvation Army choir, which is called a "Songster Brigade".When a soldier of The Salvation Army wishes to join a Songster Brigade, he or she signs an agreement and is subsequently "promoted" to the rank of songster.