editor Joseph G. E.Hopkins
Charles Scribner's Sons, 1964
Buku Referensi
Economist Books, 1991
Buku Referensi
Charles Scribner's Sons , 1981
Buku Referensi
edited by Leslie Stephen, Sidney Lee
Oxford University Press, 1950
Buku Referensi
Craven, Paul R., author
Dickenson Publishing, 1968
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