The Working Group 1 report of 2007 ( including the summary for policy makers ) included contributions by 600 authors from 40 countries , over 620 expert reviewers , a large number of government reviewers , and representatives from 113 governments . Of these , the Working Group 1 report ( including the summary for policy makers ) included contributions by 600 authors from 40 countries , over 620 expert reviewers , a large number of government reviewers , and representatives from 113 governments .