Penguin book
1948
1948
1946
1948
1947
1947
1946
1950
1951
1951
1955; 1830
1950
1948
1950-1951
1951
1951
1946
1949
1946-1950
1950-1952
1949
1951
2000-100 BCE
circa 1950
1946
1938 and 1951
1946-1948
1946
1950
1951
1948
1950
circa 1950
1949
1949
1947
1950
circa 1950
circa 1950
1951
1947
1950
1903 (original); 1982 (model)
1951
1948
1951
1950
1950-1951
1949
1950
1951