Kỷ nguyên
20th century
896
20th century,Thế kỷ 20
396
19th century
167
Thế kỷ 21,21st century
154
Thế kỷ 20,20th century
133
21st century
130
20th century,20th century
115
21st century,Thế kỷ 21
113
1945-
108
Examinations
63
19th century,Thế kỷ 19
38
Study guides
36
19th century,19th century
33
1945-,1945-
31
18th century,Thế kỷ 18
28
18th century
26
21th century
26
20th century,20th century,Thế kỷ 20,Thế kỷ 20
23
1945-1989
22
Vietnam
21
1945
20
21th century,Thế kỷ 21
20
17th century
18
1939-1945
18
1945-1975,1945-1975
16
1989-
16
20th Century
14
21st century,21st century,Thế kỷ 21,Thế kỷ 21
14
Thế kỷ 19,19th century
14
1945-1989,1945-1989
13
1954-1975
13
1961-1975,1961-1975
13
Vietnam,Việt Nam
13
20 century,Thế kỷ 20
12
1868-
10
1945-1971
10
19th century,19th century,Thế kỷ 19,Thế kỷ 19
10
20th century,thế kỷ 20
10
Civil War, 1861-1865,Nội chiến, 1861-1865
10
Outlines, syllabi, etc
10
17th century,Thế kỷ 17
9
1945-1975
9
1954-1975,1954-1975
9
1961-1975
9
19th century,20th century
9
20th century,20th century,Thế kỷ 20
9
21 century,Thế kỷ 21
9
1933-1945
8
1989-,1989-
8
20th century ( vietnamese )
8
hơn ...