S. Rexhepi, S. Kera, and H. Snopce, “ON ESTIMATION OF FOURIER AND QUASI-MONOTONE-FOURIER COEFFICIENTS OF FUNCTIONS IN NIKOL’SKII CLASSES”, Mat. Bilt., vol. 43, no. 1, pp. 79–89, Jan. 2019, doi: 10.37560/matbil1190079r.