Παραπομπή APA

Thomson South-Western. (2007). Virtual tutor system: Michigan version 3.0. Thomson South-Western.

Παραπομπή Chicago Style

Thomson South-Western. Virtual Tutor System: Michigan Version 3.0. Thomson South-Western, 2007.

Παραπομπή MLA

Thomson South-Western. Virtual Tutor System: Michigan Version 3.0. Thomson South-Western, 2007.

Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.