PARTITION OF UNITY AND THE STRONG ELLIPTICITY PROBLEM FOR FUNCTIONAL DIFFERENTIAL OPERATORS Статья Skryabin M.A. Journal of Mathematical Sciences (United States). Springer New York LLC. Том 170. 2010. С. 270-282
MODEL PROBLEM FOR AFUNCTIONAL-DIFFERENTIAL OPERATOR WITH ROTATIONS Статья Skryabin M.A. Russian Mathematical Surveys. Том 64. 2009. С. 168-169