Cita APA (7a ed.)
(1969). Environment. [Helen Dwight Reid Educational Foundation].
Cita Chicago Style (17a ed.)
Environment. [Washington, etc.]: [Helen Dwight Reid Educational Foundation], 1969.
Cita MLA (9a ed.)
Environment. [Helen Dwight Reid Educational Foundation], 1969.
Precaución: Estas citas no son 100% exactas.