Lyle, John Tillman
Van Nostrand Reinhold Company, 1985
Buku Teks
Beijer International Institute of Ecological Economics and The World Bank , 1995
Buku Teks
France, R. L. (Robert Lawrence), auhtor
CRC Press, 2012
Buku Teks
Brubaker, Sterling, author
A Mentor Book, 1972
Buku Teks
Francis, Robert A., author
Routledge, 2013
Buku Teks