
'Sitesquare' optical square, British, 1959
1959
1959
1957
1954
1970
1948-1960
1955
1950-1954
1959
1943-1948
1970
1960-1965
1970-1996
1954-1964
1959
1959
circa 1970
1961
1957
1960
1959
1948-1960
1948-1969
1967-1968
1950-1959
1949
1953-1954
1953-1954
1955
circa 1940s-circa 1950s
1959
1959
1953-1954
1905-1968
1950
1959
1960-1975
1958