Chow, J., Watson, J., Green, M., Wang, X., Chen, L., Trimble, D., … Gronstal, S. (2018). Separation of brown carbon from black carbon for IMPROVE and CSN PM<sub>2.5</sub> Samples. Journal of the Air & Waste Management Association (1995). https://doi.org/10.1080/10962247.2018.1426653 (Original work published 2018)