1. Harvard Committee,General Education in a Free Society, Cambridge , Harvard University Press , 1948 , p. 119 – 127 .
2. “Language Study and World Affairs,” An address delivered at the 35th Annual Meeting of the Central States Modern Language Teachers Association , May 3, 1952 , St. Louis , Mo.
3. Arnold J. Toynbee ,A Study of History, Abridgement of Volumes I-VI by D. C. Somervell , London , Oxford University Press , 1947 , p. 508 – 513 .