Feynman, R. P. (1988). "Está a brincar, Sr. Feynman!". Gradiva.
Chicago Style (17th ed.) CitationFeynman, Richard P. "Está a Brincar, Sr. Feynman!". Gradiva, 1988.
MLA (8th ed.) CitationFeynman, Richard P. "Está a Brincar, Sr. Feynman!". Gradiva, 1988.
Warning: These citations may not always be 100% accurate.