This work is the most extensive and credited scientific author ship in this field in the past two decade. Among the marked characteristics of this book which make it admirable, are its beautiful and engrossing prose, homogeneity and coherence in the presentation of subjects in each chapter, conformity to the methods of scientific historiography references given to all the authoreized source in the world while designating their level of credibility, extensive bibliography, index of names and documented notes provided at the end of the book.