Adragni, Kofi Placid, and Andrew M. Raim. “Ldr: An R Software Package for Likelihood-Based Sufficient Dimension Reduction”. Journal of Statistical Software 61, no. 3 (November 3, 2014): 1–21. Accessed June 30, 2024. https://www.jstatsoft.org/index.php/jss/article/view/v061i03.