Actually, that picture is closer to the early prototypes than to the final design. I have to believe that, given the sci-fi fandom going on by the people involved in the films making, and given that Lucas constantly was handing out comic books and pulp sci fi stuff as reference, that this is not a coincidence.

At the same time though, its not that original a design. I mean the whole "wedge shaped spaceship" had already been done to death. But still, this is probably one of the specific points of reference Lucas was using. Excellent find!