Citation for A fast and objective multidimensional kernel density estimation method: fastKDE

O’Brien, T. A., Kashinath, K., Cavanaugh, N. R., Collins, W. D., & O’Brien, J. P. (2016). A fast and objective multidimensional kernel density estimation method: fastKDE. Computational Statistics & Data Analysis, 101, 148–160. https://doi.org/10.1016/j.csda.2016.02.014