Gøgsig, Thomas M., author
Springer, 2012
eBooks
Foreign Languages , 1974
Buku Teks
Buzan, Tony, author
Penguin Books, 1991
Buku Teks
edited Leonard Warren and Hilary Koprowski
Wiley-Liss, 1991
Buku Teks
McPhee, Margaret, author
Allen & Unwin, 1993
Buku Referensi