![](/media/publication/image/c233ce3f29c02dcc48f31c9d82749816_b365d295d42de9847f3d2602da624b3a_0304-4076.jpg)
Franses, P.H., Boswijk, H. and Haldrup, N. (1997). Multiple unit roots in periodic autoregression Journal of Econometrics, 80:167--193.
Frank Windmeijer (1997). An R-squared measure of goodness of fit for some common nonlinear regression models Journal of Econometrics.
Frank Windmeijer (1997). Endogeneity in count data models: An application to demand for health care Journal of Applied Econometrics.