Burton, Virginia Lee. Calico the Wonder Horse; or, The Saga of Stewy Slinker.
Cambridge, MA: The Riverside Press, 1941.
Virginia Lee Burton Papers, Ax 839.

Pen and ink sketch for page 3 of Calico the Wonder Horse.
Note that both sketches were later altered. Virginia Burton Papers, Ax 839.

Series of sketches showing the progression of preliminary pen and ink sketches
to final scratchboard illustration used for page 58.
Virginia Lee Burton Papers, Ax 839.

Left, preliminary pen and ink drawing for page 1 of Calico the Wonder Horse.
Right, the revised scratchboard final illustration that was used in the book.
Virginia Lee Burton Papers, Ax 839.

Burton's sketchbooks for Calico the Wonder Horse, ca. 1940.
Virginia Lee Burton Papers, Ax 839.