Research index·Book chapterCamera10 Sep 2012DOI10.4324/9780080509310-11Book chapterCamera10 Sep 2012DOI10.4324/9780080509310-11ReadRead at the publisherSaveCiteAdd to literature reviewThe full text is at the publisherOpen it at the publisher to read it.DiscussionAdd to the discussionTopicsComputer scienceGeographyArtRelated papersMoreDetailsPublished, issue, languageSuggest a correction or report