CROSBY PHILIP B. (1980). QUALITY IS FREE THE ART OF MAKING QUALITY CERTAIN. MENTOR BOOKS.
Chicago-čujuhus (17. p.)CROSBY PHILIP B. QUALITY IS FREE THE ART OF MAKING QUALITY CERTAIN. NEW YORK: MENTOR BOOKS, 1980.
MLA-čujuhus (9. p.)CROSBY PHILIP B. QUALITY IS FREE THE ART OF MAKING QUALITY CERTAIN. MENTOR BOOKS, 1980.
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