Columbia subject headings:
Architects--United States--Correspondence.
Authors, American--20th century--Correspondence.
City planners--United States--Correspondence.
Liebovitz, David, 1892-1968--Correspondence.
Mumford, Lewis, 1895-1990--Correspondence.
Social reformers--United States--Correspondence.
Harvard subject headings:
Architects--United States--Correspondence.
Authors, American--20th century--Correspondence
City planners--United States--Correspondence.
Liebovitz, David, 1892-1968--Correspondence.
Mumford, Lewis, 1895-1990--Correspondence.
Social reformers--United States--Correspondence.
Princeton subject headings:
Architects--United States--Correspondence.
Authors, American--20th century--Correspondence.
City planners--United States--Correspondence.
Liebovitz, David, 1892-1968--Correspondence.
Mumford, Lewis, 1895-1990.
Social reformers--United States--Correspondence.