Tyack, D. B. (1967). Turning points in American educational history. Blaidsdell.
Lua i Stíl Chicago (17ú heag.)Tyack, David B. Turning Points in American Educational History. Massachusets: Blaidsdell, 1967.
Lua MLA (9ú heag.)Tyack, David B. Turning Points in American Educational History. Blaidsdell, 1967.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.