International Labour Office. (1951). Payment by results. International Labour Office.
استشهاد بنمط شيكاغوInternational Labour Office. Payment by Results. Geneva: International Labour Office, 1951.
MLA استشهادInternational Labour Office. Payment by Results. International Labour Office, 1951.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.