Zur Titelführung: vgl. Subskriptionsliste des Buches: Robert William Billings: Architectural illustrations: history and description of Carlisle cathedral (1840) [1]
N. N.: Obituary in: The Gentleman's Magazine and Historical Review January-June 1859, S. 433–434.
Antonia Brodie: Directory of British Architects 1834-1914: L-Z. British Architectural Library, Royal Institute of British Architects, 2001, S. 253 [2]
