Gray, P., & Jurison, J. (1995). Productivity in the office and the factory. Boyd & Fraser.
Lua i Stíl Chicago (17ú heag.)Gray, Paul, agus Jaak Jurison. Productivity in the Office and the Factory. Danvers, Mass: Boyd & Fraser, 1995.
Lua MLA (9ú heag.)Gray, Paul, agus Jaak Jurison. Productivity in the Office and the Factory. Boyd & Fraser, 1995.
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