1 Subjects: “...20th century...”

2 Subjects: “...20th century history: c 1900 to c 2000 / bicssc...”

3 Subjects: “...History, 20th Century...”

4 Subjects: “...History, 20th Century...”

5 Subjects: “...History, 20th Century...”

6 Subjects: “...Modern history to 20th century: c 1700 to c 1900 / bicssc...”

7 Subjects: “...Modern history to 20th century: c 1700 to c 1900...”

8 Subjects: “...History of the 20th Century...”

9 Subjects: “...20th Century...”

10 Subjects: “...Later 20th century c 1950 to c 1999 / bicssc...”

11 Subjects: “...Modern history to 20th century: c 1700 to c 1900 / bicssc...”

12 Subjects: “...Modern history to 20th century: c 1700 to c 1900 / bicssc...”

13 Subjects: “...20th century, c 1900 to c 1999 / bicssc...”

14 Subjects: “...20th century, c 1900 to c 1999...”

15 Subjects: “...thema EDItEUR::3 Time period qualifiers::3M c 1500 onwards to present day::3MP 20th century, c 1900...”

16 Subjects: “...history of the 20th century...”

17 Subjects: “...thema EDItEUR::3 Time period qualifiers::3M c 1500 onwards to present day::3MP 20th century, c 1900...”

18 Subjects: “...Modern history to 20th century: c 1700 to c 1900...”

19 Subjects: “...20th century...”

20 Subjects: “...20th century history: c 1900 to c 2000 / bicssc...”