Rohen, Johannes W.
Wolters Kluwer, 2016
Buku Referensi
Douglas J. Eder [and others]
McGraw-Hill Higher Education, 2004
Buku Referensi
Rohen, Johannes W.
Lippincott Williams & Wilkins, 2011
Buku Referensi
Miller, Marjorie A.
Macmillan, 1977
Buku Teks SO
Buku Teks