The Amstrad CP/M Plus
By: Andrew R.M.Clarke and David Powys-Lybbe.
Contributors: Powys-Lybbe, D.
Edition: Second Edition
Publisher: MML Systems Ltd
Published: 1986
Place of publication: London, UK
Language: eng
Format: Paperback
Number of pages: 518
Notes: Second Edition June 1986.

On this copy, the ISBN printed on the back cover is 1-86991-000-1.
However, the edition notice inside the book says:

> ISBN 1 869910 05 2 (paperback)
> ISBN 1 869910 00 1 (ring binder)

But this definitely is a paperback edition, not a ring binder edition.
So that's a bit confusing.