Michael Kalvius, Paul Kienle
Springer, 2012
eBooks
Taylor, Alfred Edward, 1869-1945
University Paperbacks, 1960
Buku Teks SO
Elsevier, 2013
eBooks
Ackerman, Robert
Cambridge University Press , 1990
Buku Teks SO
Moscow Foreign Languages Publishing House 1959
Buku Teks