Valery B. Kokshenev, To the problem of observation of two-level tunneling states in supercooled liquids, glass-forming polymers, orientational glasses, and metallic glasses via configurational entropy, Low Temp. Phys. 35, (2009) [Fiz. Nizk. Temp. 35, 371-375, (2009)] DOI: https://doi.org/10.1063/1.3115806.