1. Bachir, Ahmed., & Almanjahie, Ibrahim Mufrah., & Attouch, Mohammed Kadi., (2020), "The K-Nearest Neighbors Estimator of the M – Regression in Functional Statistics".
2. Blanchet, J., & Wadsworth, J., (2012), "Applied Statistics", Institute of Mathematics, Analysis, and Applications EPF Lausanne, An MSc Course for Applied Mathematicians.
3. Boente, G., & Perez, A., & Gonzalez W., (1990), "Robust Nonparametric Estimation with Missing Data", Buenos Aires University.
4. Burba, Florent., & Ferraty, Frederic., & View, Philippe., (2008), "K-Nearest Neighbors Method in Functional Nonparametric Regression", I.M.T. University Paul Sabatier, Toulouse, France.
5. Cizek, Pavel., & Sadikoglu, Serhan., (2019), "Robust Nonparametric Regression: A review,. Tiburg University.