Notes: I took this from a film scan at the Library of Congress that had ragged margins and also color reference targets.

The image was cropped to exclude such library-specific artifacts and print to a 4x6 card. Also I enlarged and contrast increased a strip of Japanese language text on the left hand side to make it visible when printed on said card.

I think the author has an anthropomorphic stylized signature which makes me think of Tsunako's panda.