Question: When was Boneland, the sequel to "The Weirdstone of Brisingamen" was written by English author Alan Garner in what year?

Context articles: Legacy (Judd novel)
The Owl Service (TV series)
The Moon of Gomrath
Elidor
The Weirdstone of Brisingamen
Key to the Door (novel)
Boneland
Habeas Corpus (play)
Alan Garner (disambiguation)
Tango (novel)

Set in 1970s London, Legacy is a spy novel by English author Alan Judd.
 Published in 2001 it continues the story of Charles Thoroughgood, first introduced in his debut novel, "A Breed of Heroes", published 20 years earlier.
 British historian Peter Hennessy described it as 'one of the best spy novels ever'.
The Owl Service is an eight-part television series based on the fantasy novel of the same name by Alan Garner.
 Produced in 1969 and televised over the winter of 1969–1970, the series was remarkably bold in terms of production.
 It was the first fully scripted colour production by Granada Television and was filmed almost entirely on location at a time when almost all TV drama was studio-bound.
 It used editing techniques such as jump cuts to create a sense of disorientation and also to suggest that two time periods overlapped.
 For the series, the book was adapted in seven scripts (later stretched to eight) by Garner and was produced and directed by Peter Plummer.
 The direction was quite radical and seemed to be influenced by the avant-garde, a noted contrast to what might be expected of a children's serial.
The Moon of Gomrath is a fantasy story by the author Alan Garner, published in 1963.
 It is the sequel to "The Weirdstone of Brisingamen".
Elidor is a children's fantasy novel by the British author Alan Garner, published by Collins in 1965.
 Set primarily in modern Manchester, it features four English children who enter a fantasy world, fulfill a quest there, and return to find that the enemy has followed them into our world.
 Translations have been published in nine languages and it has been adapted for television.
The Weirdstone of Brisingamen: A Tale of Alderley is a children's fantasy novel written by the English author Alan Garner (born 1934).
 Garner began work on the novel, his literary debut, in 1957 after he moved into the late mediaeval house Toad Hall, in Blackden, Cheshire.
 The story, which took the local legend of The Wizard of the Edge as a partial basis for the novel's plot, was influenced by the folklore and landscape of the neighbouring Alderley Edge where he had grown up.
 Upon completion the book was picked up by the publisher Sir William Collins who released it through his publishing company Collins in 1960.
Key to the Door is a novel by English author Alan Sillitoe, first published in 1961.
Boneland is a 2012 novel by Alan Garner, a sequel to "The Weirdstone of Brisingamen" and "The Moon of Gomrath".
 The boy Colin from the earlier novels is now an adult, still living near the top of Alderley Edge but now a Professor working at the nearby Jodrell Bank Observatory.
 His solitary home is a kit-built hut ("A Bergli") in a quarry.
 He has a form of amnesia which means he remembers nothing from before the age of 13, including his twin sister and his childhood adventures.
 He visits a psychotherapist and the gradual uncovering of his past forms the main story.
Habeas Corpus is a stage comedy in two acts by the English author Alan Bennett.
 It was first performed at the Lyric Theatre in London on 10 May 1973, with Alec Guinness in the central role.
 It ran, with cast changes, until 10 August 1974.
 The Broadway production that followed was less successful, running for less than three months.
 The play has been revived several times since then, in London and elsewhere.
Alan Garner is an English author.
Tango is a novel by English author Alan Judd published in 1989 by Hutchinson.
 Quentin Letts writing in "The Daily Telegraph" described it as "his funniest novel to date".