Cheng, Sui-Sun Systems-conjugate and focal points of fourth order nonselfadjoint differential equations. (English) Zbl 0339.34029 Trans. Am. Math. Soc. 223, 155-165 (1976). MSC: 34C10 PDFBibTeX XMLCite \textit{S.-S. Cheng}, Trans. Am. Math. Soc. 223, 155--165 (1976; Zbl 0339.34029) Full Text: DOI
Brown, Richard C.; Krall, Allan M. Ordinary differential operators under Stieltjes boundary conditions. (English) Zbl 0295.34010 Trans. Am. Math. Soc. 198, 73-92 (1974). MSC: 34B10 47A10 34L99 47E05 PDFBibTeX XMLCite \textit{R. C. Brown} and \textit{A. M. Krall}, Trans. Am. Math. Soc. 198, 73--92 (1974; Zbl 0295.34010) Full Text: DOI
Fennell, R. E.; Proctor, T. G. Perturbations of nonlinear differential equations. (English) Zbl 0245.34027 Trans. Am. Math. Soc. 185 (1973), 401-411 (1974). MSC: 34E10 34C10 PDFBibTeX XMLCite \textit{R. E. Fennell} and \textit{T. G. Proctor}, Trans. Am. Math. Soc. 185, 401--411 (1974; Zbl 0245.34027) Full Text: DOI
Krall, A. M. Differential-boundary operators. (English) Zbl 0217.11802 Trans. Am. Math. Soc. 154, 429-458 (1971). MSC: 34B15 47E05 PDFBibTeX XMLCite \textit{A. M. Krall}, Trans. Am. Math. Soc. 154, 429--458 (1971; Zbl 0217.11802) Full Text: DOI
Etgen, G. J. Two point boundary problems for second order matrix differential systems. (English) Zbl 0217.11701 Trans. Am. Math. Soc. 149, 119-132 (1970). MSC: 34B10 34B15 PDFBibTeX XMLCite \textit{G. J. Etgen}, Trans. Am. Math. Soc. 149, 119--132 (1970; Zbl 0217.11701) Full Text: DOI
Etgen, G. J. Oscillatory properties of certain nonlinear matrix differential systems of second order. (English) Zbl 0151.12302 Trans. Am. Math. Soc. 122, 289-310 (1966). PDFBibTeX XMLCite \textit{G. J. Etgen}, Trans. Am. Math. Soc. 122, 289--310 (1966; Zbl 0151.12302) Full Text: DOI
Cole, R. H. General boundary conditions for an ordinary linear differential system. (English) Zbl 0151.11101 Trans. Am. Math. Soc. 111, 521-550 (1964). PDFBibTeX XMLCite \textit{R. H. Cole}, Trans. Am. Math. Soc. 111, 521--550 (1964; Zbl 0151.11101) Full Text: DOI
Ablow, C. M.; Brenner, J. L. Roots and canonical forms for circulant matrices. (English) Zbl 0112.25003 Trans. Am. Math. Soc. 107, No. 2, 360-376 (1963). Reviewer: P. Dembowski MSC: 15A18 15A20 15A21 PDFBibTeX XMLCite \textit{C. M. Ablow} and \textit{J. L. Brenner}, Trans. Am. Math. Soc. 107, 360--376 (1963; Zbl 0112.25003) Full Text: DOI
Leighton, Walter; Nehari, Zeev On the oscillation of solutions of self-adjoint linear differential equations of the fourth order. (English) Zbl 0084.08104 Trans. Am. Math. Soc. 89, 325-377 (1959). PDFBibTeX XMLCite \textit{W. Leighton} and \textit{Z. Nehari}, Trans. Am. Math. Soc. 89, 325--377 (1959; Zbl 0084.08104) Full Text: DOI
Sion, Maurice On the existence of functions having given partial derivatives on a curve. (English) Zbl 0058.04801 Trans. Am. Math. Soc. 77, 179-201 (1954). PDFBibTeX XMLCite \textit{M. Sion}, Trans. Am. Math. Soc. 77, 179--201 (1954; Zbl 0058.04801) Full Text: DOI