Gaya APA

S.Nield-Gehrig, J., E.Willmann, D. (2011). Foundations of Periodontics for the Dental Hygienist (4). : Lippincott Williams & Wilkins.

Gaya MLA

S.Nield-Gehrig, Jill., E.Willmann, Donald. "Foundations of Periodontics for the Dental Hygienist". 4 : Lippincott Williams & Wilkins, 2011. Text.