TY - JOUR A1 - Kwiatkowski, D. A1 - Phillips, P.C. A1 - Schmidt, P. A1 - Shin, Y. T1 - Testing the null hypothesis of stationarity against the alternative of a unit root: How sure are we that economic time series have a unit root? Y1 - 1992 DO - 10.1016/0304-4076(92)90104-Y VL - 54 IS - 1–3 ER -