Columbia subject headings:
Census districts--United States--Handbooks, manuals, etc.
Geographical location codes--Handbooks, manuals, etc.
United States--Census--Methodology.
United States--Population--History.
Harvard subject headings:
Census districts--United States--Handbooks, manuals, etc.
Geographical location codes--Handbooks, manuals, etc.
United States--Census--Geography--Handbooks, manuals, etc.
United States--Census.
United States--Population--History.
Princeton subject headings:
Census districts--United States--Handbooks, manuals, etc.
Geographical location codes--Handbooks, manuals, etc.
United States--Census--Methodology.
United States--Population--History.