Erdélyi, Arthur The analytic theory of systems of partial differential equations. (English) Zbl 0044.09303 Bull. Am. Math. Soc. 57, 339-353 (1951). Reviewer: W. W. Sawyer MSC: 35A20 PDF BibTeX XML Cite \textit{A. Erdélyi}, Bull. Am. Math. Soc. 57, 339--353 (1951; Zbl 0044.09303) Full Text: DOI
Tikhonov, A. N.; Samarskiĭ, A. A. The equations of mathematical physics. (Уравнения математического физики) (Gleichungen der mathematischen Physik.) (Russian) Zbl 0044.09302 Moskau-Leningrad: Gosudarstv. Izdat. Tekhn.-Teor. Lit. 659 p. (1951). Reviewer: Lars Gårding (Lund) MSC: 35-01 00A06 35Jxx 35Kxx 35Lxx 35Qxx PDF BibTeX XML
Gel’fand, I. M.; Levitan, B. M. On the determination of a differential equation from its spectral function. (Über die Bestimmung einer Differentialgleichung nach ihrer Spektralfunktion.) (Russian) Zbl 0044.09301 Izv. Akad. Nauk SSSR, Ser. Mat. 15, 309-360 (1951). Reviewer: Göran Borg MSC: 34L05 PDF BibTeX XML Cite \textit{I. M. Gel'fand} and \textit{B. M. Levitan}, Izv. Akad. Nauk SSSR, Ser. Mat. 15, 309--360 (1951; Zbl 0044.09301)