Ohrtman, Franklin D.
Softswitch : architecture for VoIP / Franklin D. Ohrtman
McGraw-Hill, 2003
 Buku Teks SO
Scott, Ernest
A short history of Australia / by Ernest Scott
Oxford University Press, 1916
 Buku Teks SO
Scott, Ernest
A short history of Australia / Ernest Scott
Oxford University Press, 1920
 Buku Teks
Scott, Ernest
A short history of Australia / by Ernest Scott
Oxford University Press, 1935
 Buku Teks SO
Lower, Arthur R.M.
Colony to nation: a history of Canada
Longmans, Green, 1959
 Buku Teks SO