TY - RPRT TI - Time-series model, statistical methods, and software documentation for R–QWTREND—An R package for analyzing trends in stream-water quality AU - Aldo V. Vecchia AU - Rochelle A. Nustad PY - 2020 DO - 10.3133/ofr20201014 UR - https://pubs.usgs.gov/publication/ofr20201014 ID - ofr20201014 ER -