Montgomery, C. W. (1994). Instructor's manual with test item file to accompany Earth: Then and now (2nd ed.). Wm. C. Brown Publishers.
Παραπομπή σε μορφή Chicago (17η εκδ.)Montgomery, Carla W. Instructor's Manual with Test Item File to Accompany Earth: Then and Now. 2nd ed. Dubuque, IA: Wm. C. Brown Publishers, 1994.
Παραπομπή σε μορφή MLA (9th εκδ.)Montgomery, Carla W. Instructor's Manual with Test Item File to Accompany Earth: Then and Now. 2nd ed. Wm. C. Brown Publishers, 1994.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.