Доступные ссылки:

Harvard: Назаров, В. Е., Radostin, A. V.& Кияшко, С. Б. 2015. Self-Similar Acoustic Waves in Homogeneous Media with Different-Modulus Nonlinearity and Relaxation. Radiophysics and Quantum Electronics, 58(2), pp. 124-131, doi: 10.1007/s11141-015-9587-0