Não informado. (1939). Supervision: The magazine of industrial relations and operating management. National Association of Foremen.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিNão informado. Supervision: The Magazine of Industrial Relations and Operating Management. Burlington, Vt: National Association of Foremen, 1939.
M.L.A (8 ম সংস্করণ) উদ্ধৃতিNão informado. Supervision: The Magazine of Industrial Relations and Operating Management. National Association of Foremen, 1939.
সতর্কবাণী: সাইটেশন সবসময় 100% নির্ভুল হতে পারে না.