Axiomatic set theory is the concern of this book. More particularly, the authors prove results about the coding of models M, of Zermelo-Fraenkel set theory together with the Generalized Continuum Hypothesis by using a class 'forcing' construction. By this method they extend M to another model L a] with the same properties. L a] is G dels universe of 'constructible' sets L, together with a set of integers a which code all the cardinality and cofinality...