8Engle R F, Granger C W J. Co-integration and error correction: Representation, estimation and testing [J]. Econometrica, 1987, 55: 251-276.
9Cushing, Matthew J, Mary G, et al. Feedback between wholesale and consumer price inflation: A re-examination of the evidence [J] .Southern Economic Journal, 1990,56:1059-1072.
10Todd E" Clark. Do Producer Prices Lead Consumer Prices? [J] . Economic Review, 1995, g0(3): 25-39.