1. M. S. Agranovich, “Spectral problems for second-order strongly elliptic systems in domains with smooth and nonsmooth boundary,” Usp. Mat. Nauk, 57, No. 5 (347), 3–78 (2002).
2. M. S. Agranovich, “Remarks on potential spaces and Besov spaces in a Lipschitz domain and on Whitney arrays on its boundary,” Russ. J. Math. Phys., 15, No. 2, 146–155 (2008).
3. T. Ya. Azizov, N. D. Kopachevskii, and L. D. Orlova, “Evolution and spectral problems related to small motions of viscoelastic fluid,” Am. Math. Soc. Transl., 199, 1–24 (2000).
4. F. R. Eirich, Rheology. Theory and Applications, Academic Press, New York (1956).
5. E. Galiardo, “Caratterizzazioni delle tracce sulla frontiera relative ad alcune classi di funzioni in n variabili,” Rend. Semin. Mat. Univ. Padova, 27, 284–305 (1957).