Stephen R. Covey (1994). “Daily Reflections for Highly Effective People: Living THE SEVEN HABITS OF HIGHLY SUCCESSFUL PEOPLE Every Day”, p.281, Simon and Schuster
Stephen R. Covey (1994). “Daily Reflections for Highly Effective People: Living THE SEVEN HABITS OF HIGHLY SUCCESSFUL PEOPLE Every Day”, p.208, Simon and Schuster
Stephen R. Covey (1994). “Daily Reflections for Highly Effective People: Living THE SEVEN HABITS OF HIGHLY SUCCESSFUL PEOPLE Every Day”, p.140, Simon and Schuster
Stephen R. Covey (1994). “Daily Reflections for Highly Effective People: Living THE SEVEN HABITS OF HIGHLY SUCCESSFUL PEOPLE Every Day”, p.111, Simon and Schuster