Prokopenko, J. (1987). Productivity management: A practical handbook. International Labour Office.
Lua i Stíl Chicago (17ú heag.)Prokopenko, Joseph. Productivity Management: A Practical Handbook. Geneva: International Labour Office, 1987.
Lua MLA (8ú heag.)Prokopenko, Joseph. Productivity Management: A Practical Handbook. International Labour Office, 1987.
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