The author, Ernest Mason Satow, wrote a book in 1905 which still nowdays is a masterpiece. In his fifth edition, Lorde Gore-Booth, editor, and Desmond Pakenham, assistant editor, include in this referecial book the kind of cartesian information about United Nations that Lorde Mason would consider of deserving all his honours. Read this book must be not so much as a diplomatic decision but a decison of any human being in a diplomatic mission.