Phillips, R. S.; Sarason, L. Singular symmetric positive first order differential operators. (English) Zbl 0141.28701 J. Math. Mech. 15, 235-271 (1966). Page: −5 −4 −3 −2 −1 ±0 +1 +2 +3 +4 +5 Show Scanned Page Cited in 19 Documents Keywords:partial differential equations PDF BibTeX XML Cite \textit{R. S. Phillips} and \textit{L. Sarason}, J. Math. Mech. 15, 235--271 (1966; Zbl 0141.28701) OpenURL