Van Vlack, Lawrence H.
Addison-Wesley, 1959
Buku Teks SO
by J.C. Anderson ...[and others]
The English Language , 1982
Buku Teks SO
Chapman & Hall, 2018
Majalah, Jurnal, Buletin
Van Vlack, Lawrence H.
Addison-Wesley, 1964
Buku Teks SO
Sirvarajan, V.
Bangalore: V.K. Publisher, 1980
Buku Teks