Sestelo, M., Villanueva, N. M., Meira-Machado, L. and Roca-Pardiñas, J. (2017) “npregfast: An R Package for Nonparametric Estimation and Inference in Life Sciences”, Journal of Statistical Software, 82(12), pp. 1–27. doi: 10.18637/jss.v082.i12.