Não informado. (1976). Occupational Health and Safety. Stevens Publishing.
Lua i Stíl Chicago (17ú heag.)Não informado. Occupational Health and Safety. Waco, Tex: Stevens Publishing, 1976.
Lua MLA (8ú heag.)Não informado. Occupational Health and Safety. Stevens Publishing, 1976.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.