Não informado. (1952). Elementary school science bulletin. National Science Teachers Association.
Lua i Stíl Chicago (17ú heag.)Não informado. Elementary School Science Bulletin. Washington: National Science Teachers Association, 1952.
Lua MLA (8ú heag.)Não informado. Elementary School Science Bulletin. National Science Teachers Association, 1952.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.