ジェロントロジー・リサーチ・グループ
On 19 February 2011, she celebrated her 110th birthday, becoming a supercentenarian—one of just 10 living in the United Kingdom, all of whom were women. With the death of Claude Choules on 5 May 2011, Green became the last known living veteran of the First World War. On 20 July 2011, the Gerontology Research Group verified her age, and listed her as an official supercentenarian.