1. Eine Umkehrung der Sturm–Liouvilleschen Eigenwertaufgabe;Borg;Acta Math.,1946
2. On the inverse Sturm–Liouville problem for a non-Hermitian operator;Karaseva;Mat. Sb.,1953
3. A characterization of the spectrum of the hill operator;Marchenko;Mat. Sb.,1975
4. Sturm–Liouville Operators and their Applications;Marchenko,1977
5. Inverse Sturm–Liouville Problems;Levitan,1984