1. Babenko, K.I., Some Problems in Approximation Theory and Numerical Analysis, Uspekhi Mat. Nauk, 1985, vol. 40, no. 1, pp. 3–28.
2. Babenko, K.I., Osnovy chislennogo analiza(Fundamentals of Numerical Analysis), Moscow: Nauka, 1986.
3. Boykov, I.V., Optimal Accuracy Algorithms for Calculating Integrals, in Optimal Computation Methods and Their Application, no. 8, Penza: Penza Polytechnic Institute, 1987, pp. 4–22.
4. Boykov, I.V., Approximation of Some Classes of Functions by Local Splines, Zh. Vych. Mat. Mat. Fiz., 1998, vol. 38, no. 1, pp. 25–33.
5. Boykov, I.V., Optimal’nye metody priblizheniya funktsii i vychisleniya integralov (Optimal Methods for Approximation of Functions and Calculating Integrals), Penza: Penza State Universiity, 2007.