Small Woods Where I Met Myself by Jerry Uelsmann - 1967.
“To create the photomontage…, Jerry Uelsmann took three shots; he placed each negative in a separate enlarger, blending images by moving a single piece of printing paper from one to the other, then reversed some of the images and produced halo effects. Uelsmann has called the darkroom ‘in the truest sense, a visual research lab … . [One can] revisualize the final image at any point… . It has been and will always be alchemy.’” —Life Library of Photography: The Camera
http://www.uelsmann.net/