Lionni, L. (2009). Little blue and little yellow: A story for Pippo and Ann and other children ([50th anniversary ed.].). Alfred A. Knopf.

Lionni, Leo. Little Blue and Little Yellow: A Story for Pippo and Ann and Other Children. [50th anniversary ed.]. New York: Alfred A. Knopf, 2009.

Lionni, Leo. Little Blue and Little Yellow: A Story for Pippo and Ann and Other Children. [50th anniversary ed.]. Alfred A. Knopf, 2009.