The Economist : dictionary of political biography
Economist Books, 1991
 Buku Referensi
Dictionary of American biography
Charles Scribner's Sons , 1981
 Buku Referensi
Concise dictionary of American biography
Charles Scribner's Sons, 1964
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Dictionary of Canadian Biography
[publisher not identified], [date of publication not identified]
 Buku Teks
Wallacem W. Stewart
The dictionary of Canadian biography
Macmillan, 1945
 Buku Teks SO