18x07: 3rd August 1977
18x06: 8th June 1977
18x05: 6th June 1977
18x04: 20th April 1977
18x03: 7th March 1977
17x05: 14th July 1976
17x04: 5th April 1976
17x03: 17th March 1976
16x04: 7th July 1975