Columbia subject headings:
Architecture, Modern--20th century.
Architecture--United States--History--20th century.
John Portman & Associates.
Harvard subject headings:
Architectural firms--United States.
Architecture, Modern--21st century
Architecture--Georgia--20th century.
Architecture--United States--History--20th century
Architecture--United States--History--20th century.
John Portman & Associates.
Portman, John Calvin.
Princeton subject headings:
Architecture, Modern--20th century.
Architecture--United States--History--20th century.
John Portman & Associates.