Columbia subject headings:
Businessmen--United States--Biography.
Petroleum industry and trade--United States--History.
Smith, Roy C. (Roy Cyrus), 1896-
Harvard subject headings:
Businessmen--United States--Biography
Petroleum industry and trade--United States--History
Smith, Roy C. (Roy Cyrus), 1896-
Princeton subject headings:
Businessmen--United States--Biography.
Petroleum industry and trade--United States--History.
Smith, Roy C. (Roy Cyrus), 1896-