Reader's Digest Association , 1962
Buku Teks
Keller, Helen Rex, author
McMillan Company, 1959
Buku Referensi
Debenham, Frank, author
Reader's Digest Association, 1979
Buku Referensi
London : Raeder's Digest
Majalah, Jurnal, Buletin
Prihandini Anisa Arinal, author
2016
UI - Makalah dan Kertas Kerja