Artikel Jurnal
edited by Harold C. Gardiner
Devin-Adair Co., 1949
Buku Teks
Robert Maynard Hutchins, editor in chief
Encyclopaedia Britannica, Inc., 1952
Buku Referensi
Sally Joice
2015
UI - Skripsi (Membership)
Keller, Helen Rex
McMillan Company, 1959
Buku Referensi