Fraenkel, J. R., & Wallen, N. E. (2019). How to design and evaluate research in education. McGraw-Hill.
Παραπομπή σε μορφή Chicago (17η εκδ.)Fraenkel, Jack R., και Norman E. Wallen. How to Design and Evaluate Research in Education. Boston: McGraw-Hill, 2019.
Παραπομπή σε μορφή MLA (9th εκδ.)Fraenkel, Jack R., και Norman E. Wallen. How to Design and Evaluate Research in Education. McGraw-Hill, 2019.