Era
20th century
38
Early works to 1800
27
1922-
15
1900-1995
13
17th century
11
Quaternary
11
1562-1633
10
19th century
10
1887-1936
9
Mesozoic
8
Song dynasty, 960-1279
8
1879-1955
7
1926-
7
1936-
7
1031-1095
6
1809-1882
6
1890-1974
6
960-1644
6
Cenozoic
6
Cretaceous
6
Pleistocene
6
Qing dynasty, 1644-1912
6
Tertiary
6
To 221 B.C.
6
1587-approximately 1666
5
1839-1928
5
1911-2004
5
1937-2006
5
Paleozoic
5
Permian
5
To 1644
5
1910-1985
4
1912-1949
4
1912-1997
4
21st century
4
Devonian
4
Ordovician
4
1600-1699
3
1644-1912
3
1886-1948
3
18th century
3
1900-1999
3
1925-1980
3
78-139
3
Ming dynasty, 1368-1644
3
Triassic
3
active 13th century
3
1231-1316
2
1623-1688
2
1633-1721
2
more ...