Dezin, A. A.; Erugin, N. P.; Kudryavtsev, L. D. Sergei L’vovich Sobolev (on his sixtieth birthday). (English) Zbl 0234.01010 Differ. Equations 4 (1968), 889-892 (1972). MSC: 01A70 PDFBibTeX XMLCite \textit{A. A. Dezin} et al., Differ. Equations 4, 889--892 (1972; Zbl 0234.01010)
Dezin, A. A.; Erugin, N. P.; Kudryavtsev, L. D. Sergeĭ L’vovich Sobolev (on his 60th birthday). (Russian) Zbl 0164.00506 Differ. Uravn. 4, 1724-1730 (1968). MSC: 01A70 PDFBibTeX XMLCite \textit{A. A. Dezin} et al., Differ. Uravn. 4, 1724--1730 (1968; Zbl 0164.00506)