M. I. Bagatskii, D. Szewczyk, A. Jeżowski, V. V. Sumarokov, M. S. Barabashko, and P. V. Mateychenko, Low-temperature heat capacity of modified multiwalled carbon nanotubes with diameter 9.4 nm, Low Temp. Phys. 51, (2025) [Fiz. Nyzk. Temp. 51, 1523–1528, (2025)].