Iggland, B. (1987). Customer evaluations for industrial product development. Dept. of Management and Economics, Linköping University.
Lua i Stíl Chicago (17ú heag.)Iggland, Benny. Customer Evaluations for Industrial Product Development. Linköping: Dept. of Management and Economics, Linköping University, 1987.
Lua MLA (8ú heag.)Iggland, Benny. Customer Evaluations for Industrial Product Development. Dept. of Management and Economics, Linköping University, 1987.
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