Data-driven local polynomial for the trend and its derivatives in economic time series
Y. Feng, T. Gries, M. Fritz, Journal of Nonparametric Statistics (2020) 510–533.

Data-driven local polynomial for the trend and its derivatives in economic time series
Y. Feng, T. Gries, M. Fritz, Journal of Nonparametric Statistics (2020) 510–533.

On the asymptotic variance in nonparametric regression with fractional time-series errors
Y. Feng, Journal of Nonparametric Statistics 19 (2007) 63–76.