1981
January January ; 28 (1) : 1 - 103	March March ; 28 (2) : 105 - 198	May May ; 28 (3) : 201 - 300
July July ; 28 (4) : 301 - 419	September September ; 28 (5) : 421 - 519	November November ; 28 (6) : 521 - 653