08/1977-04/1979
04/1979-04/1982
04/1979-08/1980
04/1979-02/1983
03/1978-04/1979
12/1979-04/1982
)BU20..TR..ST ; (7708- )BU22,36,37..TR ; (7708- )BU21,23,25,30,31,32,33,34,35,4#
