Bulletin no. 21 (August 1974)
Bulletin no. 31 (January 1978)
Bulletin no. 22 (January 1975)
Bulletin no. 32 (March 1978)
Bulletin no. 23 (March 1975)
Bulletin no. 33 (September 1978)
Bulletin no. 24 (August 1975)
Bulletin no. 34 (January 1979)
Bulletin no. 25 (October 1975)
Bulletin no. 35 (April 1979)
Bulletin no. 26 (February 1976)
Bulletin no. 36 (July 1979)
Bulletin no. 27 (July 1976)
Bulletin no. 37 (November 1979)
Bulletin no. 28 (November 1976)
Bulletin no. 38 (April 1980)
Bulletin no. 29 (March 1977)
Bulletin no. 39 (September 1980)
Bulletin no. 30 (September 1977)
Bulletin no. 40 (December 1980)
