Não informado. (1952). Work study. Institute of Industrial Technicians.
Lua i Stíl Chicago (17ú heag.)Não informado. Work Study. London: Institute of Industrial Technicians, 1952.
Lua MLA (8ú heag.)Não informado. Work Study. Institute of Industrial Technicians, 1952.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.