1989 April 16, Joseph Michalak, Stephen S. Pickering, Louis Uchitelle, quoting Harris L. Sussman, “Experts Divided On Jobs in the 90's”, in The New York Times
2015, Richard Eleftherios Boyatzis, Kylie Rochford, Scott N. Taylor, editors, The Impact of Shared Vision on Leadership, Engagement, Organizational Citizenship and Coaching, page 145