Great Britain. Dept. of the Environment. Headquarters Library & Walsh, J. V. (1975). Historic buildings: Preservation policy. The Library.
Chicago-referens (17:e uppl.)Great Britain. Dept. of the Environment. Headquarters Library och Joan V. Walsh. Historic Buildings: Preservation Policy. [London: The Library, 1975.
MLA-referens (8:e uppl.)Great Britain. Dept. of the Environment. Headquarters Library och Joan V. Walsh. Historic Buildings: Preservation Policy. The Library, 1975.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.