Segementation du marche du travail: les developpements theoriques en Italie et premieres hypotheses pour la preparation d'un modele operationnel a verifier dans un marche du travail au niveau local = Segmentation of the labor market: theoretical developments in Italy and first assumptions for the preparation of an operational model to be verified in the labor market at the local level. Programme of research and actions on the development of the labor market. V/2764/82-F