On Obtaining Correct Input:A New Approach Most information put into machine readable form, whether from scientific or business origins, is still keypunched. This paper is addressed toward the difficulty of obtaining correctly keypunched and key verified data and an alternative method is suggested in which the computer itself is used to rule out the possibility of errors in input. This technique is explained and illustrated by reference to a working program which involves essentially two phases: in the first phase errors are detected by the machine, and subsequently, in the second phase, they are corrected by it. CACM July, 1969 Kennedy, M. correct data, correct input, data correction, keypunch, key verifier, verifier 2.40 2.42 2.43 3.10 3.20 3.50 4.41 CA690712 JB February 15, 1978 6:43 PM 1868 5 1868 1868 5 1868 1868 5 1868