The Kerven Retelling 2011
Arthurian Legends - by Rosalind Kerven
Published by the National Trust, 2011, 224 pages
This volume of seven Arthurian tales includes a 26 page abridged version of Sir Gawain and the Green Knight. Volume also has a large supplementary note section which discusses the seven stories and Arthurian tales in general, along with a bibliography and list of external sources.
This version of Sir Gawain and the Green Knight is heavily abridged and liberty is taken with story elements.
Amazon page Arthurian Legends