TY  - RPRT
TI  - Spectral rigidity for degenerate integrable systems.
AU  - D Biswas
AU  - M Azam
AU  - SV Lawande
PY  - 1991
DO  - 10.1103/physreva.43.5694
UR  - https://pubmed.ncbi.nlm.nih.gov/9904885/
ID  - 9904885
ER  -