1. Cohen AR (1964) Attitude change and social influence. Basic Books, New York
2. Evans KM (1965) Attitudes and interests in education. Routledge and Kagan, London
3. Finánczy E (1906) History of education in ancient times (in Hungarian). Hornyánszky, Budapest
4. Gordon T (1974) TET— Teacher effectiveness training. Wyden, New York
5. Ösler W (1932) On the educational value of the medical society. Acquanimitas, 3rd Ed. Blakiston's, Philadelphia, p 333