Columbia subject headings:
Buildings--Maintenance--History--Congresses.
Cultural property--Protection--History--Congresses.
Historic buildings--Conservation and restoration--Congresses.
Historic preservation--History--Congresses.
Harvard subject headings:
Buildings--Maintenance--History--Congresses.
Cultural property--Protection--History--Congresses.
Historic buildings--Conservation and restoration--Congresses.
Historic preservation--History--Congresses.
Princeton subject headings:
Buildings--Maintenance and repair--History--Congresses.
Cultural property--Protection--History--Congresses.
Historic buildings--Conservation and restoration--Congresses.
Historic preservation--History--Congresses.