Edmond Casarella was an early experimenter using cardboard shapes to build up the surface of a plate and print the surface relief, unlike a traditional relief print, which is cut away and the surface that remains is what is printed.
Casarella's techniques are well described by David Acton on page 242 of "A Spectrum of Innovation, Color in American Printmaking" Worcester Art Museum, 1990. ISBN: 0-393-02901-8.
For more information about the artist see our biography above.