1981
January Vol 67, Num 1: 1 - 166; A68 - A80	February Vol 67, Num 2: 167 - 312; A26 - A26	March Vol 67, Num 3: 313 - 446
April Vol 67, Num 4: 447 - 584	May Vol 67, Num 5: 585 - 784	June Vol 67, Num 6: 785 - 942
July Vol 68, Num 1: 1 - 153	August Vol 68, Num 2: 157 - 307; A54 - A54	September Vol 68, Num 3: 313 - 473
October Vol 68, Num 4: 475 - 616	November Vol 68, Num 5: 619 - 753	December Vol 68, Num 6: 755 - 914