Bade, William G. An operational calculus for operators with spectrum in a strip. (English) Zbl 0050.34303 Pac. J. Math. 3, 257-290 (1953). PDFBibTeX XMLCite \textit{W. G. Bade}, Pac. J. Math. 3, 257--290 (1953; Zbl 0050.34303) Full Text: DOI
Krasnosel’skij, M. A. Die Anwendung von Variationsmethoden beim Problem der Bifurkationspunkte. (Russian) Zbl 0050.34302 Mat. Sb., N. Ser. 33(75), 199-214 (1953). PDFBibTeX XMLCite \textit{M. A. Krasnosel'skij}, Mat. Sb., Nov. Ser. 33(75), 199--214 (1953; Zbl 0050.34302) Full Text: EuDML
Cronin, Jane Analytic functional mappings. (English) Zbl 0050.34301 Ann. Math. (2) 58, 175-181 (1953). PDFBibTeX XMLCite \textit{J. Cronin}, Ann. Math. (2) 58, 175--181 (1953; Zbl 0050.34301) Full Text: DOI