Baxter, E. L., Flender, M., & Landes, S. (1989). A literature guide to Sylvester and the magic pebble and Amos and Boris by William Steig. Book Wise.
Lua i Stíl Chicago (17ú heag.)Baxter, Edith Lorraine, Molly Flender, agus Sonia Landes. A Literature Guide to Sylvester and the Magic Pebble and Amos and Boris by William Steig. Cambridge: Book Wise, 1989.
Lua MLA (9ú heag.)Baxter, Edith Lorraine, et al. A Literature Guide to Sylvester and the Magic Pebble and Amos and Boris by William Steig. Book Wise, 1989.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.