Não informado. (1966). Air Pollution Titles. Pennsylvania State University, Center for Air Environmental Studies.
Lua i Stíl Chicago (17ú heag.)Não informado. Air Pollution Titles. University Park, Pa: Pennsylvania State University, Center for Air Environmental Studies, 1966.
Lua MLA (8ú heag.)Não informado. Air Pollution Titles. Pennsylvania State University, Center for Air Environmental Studies, 1966.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.