Παραπομπή σε μορφή APA (7η εκδ.)

Galle, J., & Warren, P. (1989). Ecology discovery activities kit: A complete teaching unit for grades 4-8. Center for Applied Research in Education.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Galle, Janet, και Patricia Warren. Ecology Discovery Activities Kit: A Complete Teaching Unit for Grades 4-8. West Nyack, N.Y: Center for Applied Research in Education, 1989.

Παραπομπή σε μορφή MLA (9th εκδ.)

Galle, Janet, και Patricia Warren. Ecology Discovery Activities Kit: A Complete Teaching Unit for Grades 4-8. Center for Applied Research in Education, 1989.