Hull, Jane Dee. „The Challenge of Public Service“. The Power of Character. Los Angeles, California: Josephson Institute Center for Public Service Ethics. 17-aprel 2009-yilda asl nusxadan arxivlangan. Qaraldi: 21-aprel 2009-yil.
Hull, Jane Dee. „The Challenge of Public Service“. The Power of Character. Los Angeles, California: Josephson Institute Center for Public Service Ethics. 17-aprel 2009-yilda asl nusxadan arxivlangan. Qaraldi: 21-aprel 2009-yil.