COVEY STEPHEN R. (1997). SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. SIMON & SCHUSTER INC.
Chicago Style aipamenaCOVEY STEPHEN R. SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. U.K: SIMON & SCHUSTER INC, 1997.
MLA aipamenaCOVEY STEPHEN R. SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. SIMON & SCHUSTER INC, 1997.
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