Era
1945-
16
20th century
10
1949-
7
1976-
5
1966-
4
1979-
3
1900-
2
1942-1949
2
1959-
2
1985-
2
1478-1798
1
1775 - 1783
1
1783 - 1789
1
17th century
1
1800-1837
1
1837-1901
1
1857-1919
1
1866-1953
1
1871-1918
1
1879-1953
1
1893-
1
18th century
1
1901-1936
1
1917-1936
1
1918-1933
1
1924-
1
1929-
1
1933-1945
1
1936-1956
1
1937-1979
1
1943
1
1945 -
1
1945 -Congresses
1
1945-1989
1
1946-
1
1946-1973
1
1946-1986
1
1960
1
1960-1980
1
1970 -
1
1975-
1
1976
1
1976-1990
1
1982
1
1985-1991
1
1989 - Periodicals
1
1989-
1
1990 - Periodicals
1
19th century
1
20th Century
1
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