GMU has same paper of same title but dated later. This is the earliest known version, dated 31 May 1978. It was a draft paper prepared by John for the NSF Project on a USER'S GUIDE TO PUBLIC SYSTEMS METHODOLOGY. Page one of this draft contains the list of Warfield's colleagues to whom he sent copies asking for comment: SEE ALSO the record in Textual Materials table titled: "Understanding Delta Charts" for a later version of this paper. SEE ALSO a cell-pack TRANSPARENCIES FOR "UNDERSTANDING DELTA CHARTS" which contains enlarged page-size figures of the eleven illustrations. To: Distribution From: J. N. Warfield Subject: Paper on Understanding DELTA Charts The subject paper is sent to you for your interest and possible comments. Thank you . • Distribution: R. S. Bloomfield ES&S Mark Inglis ES&S M. E. Liggan ES&S D. Rajala ES&S A. P. Sage ES&S W. Thissen ES&S Copies: J. N. Warfield (5) W. Bogan A. Christakis R. Fitz J. E. Gibson