V. F. Babenko, V. A. Kofanov, S. A. Pichugov, “On inequalities of Landau–Kolmogorov–Hörmander type on the semi-axis”, Mat. Zametki, 65:2 (1999), 175–185; Math. Notes, 65:2 (1999), 144–152
1998
3.
V. F. Babenko, V. A. Kofanov, S. A. Pichugov, “Additive inequalities for intermediate derivatives of differentiable mappings of Banach spaces”, Mat. Zametki, 63:3 (1998), 332–342; Math. Notes, 63:3 (1998), 293–301
V. F. Babenko, V. A. Kofanov, “Polynomials of fixed sign that deviate least from zero in the spaces $L_p$”, Mat. Zametki, 37:2 (1985), 176–185; Math. Notes, 37:2 (1985), 99–105
V. A. Kofanov, “Approximation in the mean of classes of differentiable functions by algebraic polynomials”, Izv. Akad. Nauk SSSR Ser. Mat., 47:5 (1983), 1078–1090; Math. USSR-Izv., 23:2 (1984), 353–365
V. A. Kofanov, “Approximation in the mean of classes of differentiable functions by algebraic polynomials”, Dokl. Akad. Nauk SSSR, 262:6 (1982), 1304–1306
1980
7.
V. A. Kofanov, “Best uniform approximation of differentiable functions by algebraic polynomials”, Mat. Zametki, 27:3 (1980), 381–390; Math. Notes, 27:3 (1980), 190–195