Drew, D. E. (1978). Competency, careers, and college. Jossey-Bass.
Lua i Stíl Chicago (17ú heag.)Drew, David E. Competency, Careers, and College. San Francisco: Jossey-Bass, 1978.
Lua MLA (9ú heag.)Drew, David E. Competency, Careers, and College. Jossey-Bass, 1978.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.