Fehr, H. F. (1963). Mathematics to-day: A guide for teachers : proceedings of an international working session on new teaching methods for school mathematics, Athens 17th-23rd November, 1963. Organisation for Economic Co-operation and Development.
Παραπομπή σε μορφή Chicago (17η εκδ.)Fehr, Howard F. Mathematics To-day: A Guide for Teachers : Proceedings of an International Working Session on New Teaching Methods for School Mathematics, Athens 17th-23rd November, 1963. [s.l.]: Organisation for Economic Co-operation and Development, 1963.
Παραπομπή σε μορφή MLA (9th εκδ.)Fehr, Howard F. Mathematics To-day: A Guide for Teachers : Proceedings of an International Working Session on New Teaching Methods for School Mathematics, Athens 17th-23rd November, 1963. Organisation for Economic Co-operation and Development, 1963.