Wehr, Hans, 1909-1981, author
Spoken Language Services, 1976
Buku Referensi
Lewis, Norman
New York Harper and Row 1963
Buku Referensi
Collins Clear-Type Press, 1960
Buku Referensi
edited by Jess Stein
Dell Publishing, 1962
Buku Referensi
Theodorson, George A
Buku Teks