Bennett, H. H. (Hugh Hammond), 1881-1960, author
McGraw-Hill, 1955
Buku Teks
Young, Anthony, author
Oxon CAB International, 1994
Buku Teks
Van Dersel, William Richard, author
Oxford University Press, 1946
Buku Teks
edited by D.J. Greenland and R. Lal
John Wiley & Sons, 1979
Buku Teks
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