I Found Cleopatra was one of two Thrilling Novels published by Export in 1946 for the post war British market. The story was first seen in the American pulp Weird Tales as a four part serial from November 1938 to February 1939. Export's edition is approximately 30% shorter. The Weird Tales version was also published by Fax Collector's Editions: Linn, Oregon, 1977.
The modern example is Orion Books's Moby-Dick: in half the time (1/2), one of a twelve book Compact Editions series. The twist is ;or The Whale (;) created by Damion Searls using the Penguin edition of the Northwestern University Press edition of Moby Dick or The Whale (M). The relationship is described in The Review of Contemporary Fiction Summer 2009 issue as:
; = M - 1/2.
A couple of examples. The 15 pages of M's chapter 32 "Cetology" are missing from 1/2; one of the 566 words in chapter 62 "The Dart" is missing from 1/2 - "hapless". All of M's chapter 32 is in ; and ;'s chapter 62 is "hapless".