Nelson, C. R. and Plosser, C. I. 1982 Trens and random walks in marcoeconomics time seies, Journal of Monetary Economics, Vol. 10: PP139-162
Nelson, C. R. and Plosser, C. I. 1982 Trends and random walks in macroeconomic time series: some evidence and  implications, Journal of Monetary Economics, Vol.10:PP139-162
谢谢了！