Lindeman, Ralph D
Norman Douglas
Twayne Publishing, 1965
 Buku Teks
Stroud, Angus
Stuart England
Routledge, 1999
 Buku Teks SO
Serat Co Jo (Tyo Jo)
[Publisher not identified], [Date of publication not identified]
 Naskah
Llyod, Douglas
Alicyclic compounds / Douglas Llyod
American Elsevier , 1963
 Buku Teks
Douglas, Colin
Sickness and health/ Colin Douglas
Heinemann, 1991
 Buku Teks SO