1981-01-25 /decus_20tap2_198111/01/decus/20-0046/abacus.exe 1981-01-25 /decuslib20-02/01/decus/20-0046/abacus.exe 1981-02-22 /decus_20tap2_198111/01/decus/20-0076/abacus.exe 1981-02-22 /decuslib20-02/01/decus/20-0076/abacus.exe