By following the lines twice (but not exactly) you can achieve a sort of vibration with two opposing colors. For this lithograph a dozen color propositions (proofs) were spread out to tempt me. I hope I chose the best one.    

     –from Dorothea Tanning: Hail Delirium! A Catalogue Raisonné of the Artist’s Illustrated Books and Prints, 1942-1991, New York: The New York Public Library, 1992, p.100.