Edward L. Ferman. Bigfoot in Maine. PR with extraterrestrials and time traveller. J. G. the Upright Ape. Lyle Stuart, 1960.
Humanized ape looks at humanity.
Smith, L. Neil. The Probability Broach. The Venus Belt, s.p., 1981. PR among Neanderthalers in Pennsylvania. Everett F. Bleiler and T.E. Dikty.