Não informado. (1967). Earth and Mineral Sciences. Pennsylvania State College, College of Earth and Mineral Sciences.
Lua i Stíl Chicago (17ú heag.)Não informado. Earth and Mineral Sciences. University Park, Pa: Pennsylvania State College, College of Earth and Mineral Sciences, 1967.
Lua MLA (8ú heag.)Não informado. Earth and Mineral Sciences. Pennsylvania State College, College of Earth and Mineral Sciences, 1967.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.