G. and F. Lenglart, «U n nouvel indicateur pour saisir les retournements de conjoncture», Économ ie et Statistique, 1998.

S. To, C. J. , M. W. Watson, F. Blanchard, and . Ish-e-r, 1989: «New indexes of coincident and leading economic indicators» in

S. To, C. J. , and M. W. Watson, «A probability model of coincident economic indicators » inLAHIRI and MOORE(sous la dir. de), L eading econom ic indicators: new approaches and forecasting m ethods , E d, 1991.

S. To, C. J. , and M. W. Tso-n, «A procedure for predicting reces sions with leading indicators: econometric issues and recent experience», inB usiness Cycles, Indicators and Forecasting, 1993.