Atwater, R., Lawson, R., & Atwater, F. (1938). Mr. Popper's penguins. Little, Brown and Company.
Lua i Stíl Chicago (17ú heag.)Atwater, Richard, Robert Lawson, agus Florence Atwater. Mr. Popper's Penguins. Boston: Little, Brown and Company, 1938.
Lua MLA (9ú heag.)Atwater, Richard, et al. Mr. Popper's Penguins. Little, Brown and Company, 1938.
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