Preston, Paul
Dorsey Press, 1986
Buku Teks SO
Thomas, Hugh
Harper & Brothers, 1961
Buku Teks SO
Payne, Stanley G.
W.W. Norton, 1970
Buku Teks SO
Arango, E. Ramon
Westview Press, 1978
Buku Teks SO
Orwell, George, 1903-1950
Mariner Books, 2015
Buku Teks SO