Dyfyniad APA

COVEY STEPHEN R. (1997). SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. SIMON & SCHUSTER INC.

Dyfyniad Arddull Chicago

COVEY STEPHEN R. SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. U.K: SIMON & SCHUSTER INC, 1997.

Dyfyniad MLA

COVEY STEPHEN R. SEVEN HABITS OF HIGHLY EFFECTIVE PEOPLE. SIMON & SCHUSTER INC, 1997.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.