Greenleaf, R K., Spears, L C., Covey, S R., & Senge, P M. [2002]. Servant leadership: A journey into the nature of legitimate power and greatness(25th anniversary edition.). New York: Paulist Press.

Servant leadership : A journey into the nature of legitimate power and greatness / essays by Robert K. Greenleaf ; edited by Larry C. Spears ; foreword by Stephen R. Covey ; afterword by Peter M. Senge . — 25th anniversary edition.. — New York : Paulist Press, [2002]. — x, 370 Seiten; 23 cm. — ISBN 0809105543, 9780809105540