Παραπομπή σε μορφή APA (7η εκδ.)

Eckel, K., & Schulze, H. (1993). Instruction language: Foundations of a strict science of instruction. Educational Technology Publications.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Eckel, Karl, και Hans-Joachim Schulze. Instruction Language: Foundations of a Strict Science of Instruction. Englewood Cliffs, N.J.: Educational Technology Publications, 1993.

Παραπομπή σε μορφή MLA (9th εκδ.)

Eckel, Karl, και Hans-Joachim Schulze. Instruction Language: Foundations of a Strict Science of Instruction. Educational Technology Publications, 1993.