Kitchen, Richard L.
John Wiley & Sons, 1986
Buku Teks
Banco Mundial, 2007
Buku Teks
Doris Kohn, editor
[Springer, Springer], 2012
eBooks
Hicks, Ursula K.
Clarendon Press, 1961
Buku Teks
Poulsen, Lauge N. Skovgaard
Cambridge University Press, 2015
Buku Teks