Perkin, H. J. (1996). The Third Revolution: Professional elites in the modern world. Routledge.
Lua i Stíl Chicago (17ú heag.)Perkin, Harold James. The Third Revolution: Professional Elites in the Modern World. London: Routledge, 1996.
Lua MLA (9ú heag.)Perkin, Harold James. The Third Revolution: Professional Elites in the Modern World. Routledge, 1996.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.