Não informado. (1952). Elementary school science bulletin. National Science Teachers Association.
Cita Chicago Style (17a ed.)Não informado. Elementary School Science Bulletin. Washington: National Science Teachers Association, 1952.
Cita MLA (8a ed.)Não informado. Elementary School Science Bulletin. National Science Teachers Association, 1952.
Precaución: Estas citas no son 100% exactas.