By September 1904
c.1905
May 1938
September 1950
August 1951
May 1956
June 1959
c early 1960s
April 1961
Mid 1960s
July 1967
1968
July 1974
August 1977
September 1977
October 1977
June 1984
January 1990
April 2010
[Source: Paul Wright]