COVEY STEPHEN R. (1997). SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. SIMON & SCHUSTER INC.
Chicago (17e ed.) BronvermeldingCOVEY STEPHEN R. SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. U.K: SIMON & SCHUSTER INC, 1997.
MLA (9e ed.) BronvermeldingCOVEY STEPHEN R. SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. SIMON & SCHUSTER INC, 1997.
Let op: Deze citaties zijn niet altijd 100% accuraat.