Did Robert Johnson really sell his soul?

Rock Expose arguing that Robert Johnson sold his soul to the Devil in exchange for guitar playing powers.

Robert Johnson and The Devil Midnight. Crossroads. Robert Johnson had sold his soul to the...
Robert Johnson: The Legend Legend tells that Robert Johnson, the father of the delta...
Robert Johnson – Me and the Devil Blues www.inekegoes.nl Robert Johnson – Me and the Devil Blues By...
Play Guitar Like Robert Johnson – CrossGuitar Playing Method by Gene Roebuck Learn to Play Guitar Like Robert Johnson go to www.crossguitar.com...
Robert Johnson Movie RARE * The Robert Johnson Blues Foundation (heirs of the Robert...