APA (7th ed.) Citation
Grotjahn, R., & Hopkins, E. (1980). Empirical Research on language teaching and language acquisition. Brockmeyer.
Chicago Style (17th ed.) Citation
Grotjahn, Ruediger, and E. Hopkins. Empirical Research on Language Teaching and Language Acquisition. Bochum: Brockmeyer, 1980.
MLA (9th ed.) Citation
Grotjahn, Ruediger, and E. Hopkins. Empirical Research on Language Teaching and Language Acquisition. Brockmeyer, 1980.
Warning: These citations may not always be 100% accurate.