Tsekanovskij, Eh. R.; Shmul’yan, Yu. L. Questions in the theory of the extension of unbounded operators in rigged Hilbert spaces. (English. Russian original) Zbl 0481.47008 J. Sov. Math. 12, 283-310 (1979); translation from Itogi Nauki Tekh., Ser. Mat. Anal. 14, 59-100 (1977). MSC: 47A70 47B15 47A10 46C20 47B50 PDFBibTeX XMLCite \textit{Eh. R. Tsekanovskij} and \textit{Yu. L. Shmul'yan}, J. Sov. Math. 12, 283--310 (1977; Zbl 0481.47008); translation from Itogi Nauki Tekh., Ser. Mat. Anal. 14, 59--100 (1977) Full Text: DOI
Klaus, M. On the bound state of Schrödinger operators in one dimension. (English) Zbl 0427.47033 Ann. Phys. 108, 288-300 (1977). MSC: 47E05 47A55 34L99 81Q10 81Q15 PDFBibTeX XMLCite \textit{M. Klaus}, Ann. Phys. 108, 288--300 (1977; Zbl 0427.47033) Full Text: DOI