Columbia subject headings:
Architects--Canada--Biography.
Architects--England--Biography.
Architecture--Canada--History--19th century.
Thomas, William, 1799-1860.
Harvard subject headings:
Architects--Canada--Biography.
Architects--England--Biography
Architecture, Modern--19th century
Architecture, Modern--19th century--Canada.
Thomas, William, 1799-1860
Princeton subject headings:
Architects--Canada--Biography.
Architecture, Modern--19th century--Canada.
Thomas, William, 1799-1860.