John A. Wheeler,  “Geons”, in Physical Review, 97 No. 2 pp. 511–536, January 15, 1955. Original wrappers, the edges of the covers of which are somewhat sunned; also there's a large-ish owner's name stamped on the front cover. VG copy. $175
“In theoretical general relativity, a geon is an electromagnetic or gravitational wave which is held together in a confined region by the gravitational attraction of its own field energy. They were first investigated theoretically in 1955 by J. A. Wheeler, who coined the term as a contraction of "gravitational electromagnetic entity"--Wikipedia, “Geons”