Não informado. (2011). Work Study & Management Services. Institute of Practitioners in Work Study, Organization and Methods.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Work Study & Management Services. Middlesex, Inglaterra: Institute of Practitioners in Work Study, Organization and Methods, 2011.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Work Study & Management Services. Institute of Practitioners in Work Study, Organization and Methods, 2011.
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