APA aipamena

Willis, S. L. (1990). Maintaining professional competence: Approaches to career enhancement, vitality, and success throughout a work life. Jossey-Bass Publishers.

Chicago Style aipamena

Willis, Sherry L. Maintaining Professional Competence: Approaches to Career Enhancement, Vitality, and Success Throughout a Work Life. San Francisco: Jossey-Bass Publishers, 1990.

MLA aipamena

Willis, Sherry L. Maintaining Professional Competence: Approaches to Career Enhancement, Vitality, and Success Throughout a Work Life. Jossey-Bass Publishers, 1990.