(2010). What's the difference?: An endangered animal subtraction story. Sylvan Dell Publishing.
Chicago-Zitierstil (17. Ausg.)What's the Difference?: An Endangered Animal Subtraction Story. Mount Pleasant, S.C: Sylvan Dell Publishing, 2010.
MLA-Zitierstil (9. Ausg.)What's the Difference?: An Endangered Animal Subtraction Story. Sylvan Dell Publishing, 2010.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.