The Dateline Comicdom Fanzine Series was published by Mike Raub, Robert Klein and Bob Greene in USA between August 1963, thru to 1977, running for 34 editions over this timeframe.
Multiple editors and writers contributed to the 34 editions released. Early Dateline Comicdom Fanzines were often limited to a print run of only 50 copies with later issues not exceeding 200 copies.
The Phantom appeared in Dateline Comicdom Fanzine edition number 29, published in 1971, containing 18 pages.
Thank you Christopher Smith for assisting with images and information.