This is an excerpt from the Library of Congress Subject Headings, showing 
examples of subheadings, related terms [RT], narrower terms [NT], broader 
terms [BT] and USE FOR corrections of former subject headings.
<pre> 
BRAZIL
  RT  Brazilians
  --Antiquities
	NT  Almeida Site (Brazil)
	    Barao do Iriri Site (Brazil)
            Casa de Pedra Cave (Brazil)
...
  --Armed Forces (May Subdivide Geographically)
    --Political activity
	NT  Tenentismo
  --Church History
    --To 1822
  --Civilization
	NT  Africa, West--Civilization--Brazilian influences
            Angola--Civilization--Brazilian influences
            English literature--Brazilian influences
            France--Civilization--Brazilian influences
    --African influences
	UF  Brazil--Civilization--Negro influences [former heading]
	BT  Africa--Civilization
...
  -- Description and Travel
    --To 1900 [F2511-F2513]
    --1901-1950 [F2515]
    --1951-1980 
    --1981-
    -Diplomatic and Consular Service
	USE Diplomatic and Consular Service, Brazil
  --Economic conditions
    --19th century
    --1918-
    --1945-
    --1945-1964
    --1964-1985
    --1985-
...
(etc.)
</pre>