Flavin, Christopher, author
Worldwatch Institute , 1986
Buku Teks
Grosvenor Press International, 1987
Buku Teks
Padolecchia, Siro P.
Vikas Publishing House, 1979
Buku Teks
Miro, Carmen A.
Frances Pinter Publ., 1980
Buku Teks
Min, Brian, 1975-, author
NY Cambridge University Press, 2015
Buku Teks