Vidon, Philippe, Hilary Hubbard, Pilar Cuadra, and Matthew Hennessy. “Storm NO<sub;>3</sub>^- and NH<sub;>4</sub><sup>+</Sup> Exports in Stream, Overland Flow, and Tile Drains of the US Midwest”. Annals of Environmental Science 6 (September 19, 2012). Accessed September 22, 2023. https://openjournals.neu.edu/aes/journal/article/view/v6art5.