Não informado. Harvard soil mechanics series. Harvard University.
Lua i Stíl Chicago (17ú heag.)Não informado. Harvard Soil Mechanics Series. Cambridge, Mass: Harvard University.
Lua MLA (8ú heag.)Não informado. Harvard Soil Mechanics Series. Harvard University.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.