@article{PismaZhETF.39.78,
    title = {Quantum systems with identical energy spectra},
    author = {Andrianov, A. A. and Borisov, N. V. and Ioffe, M. V.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {39},
    issue = {2},
    pages = {78},
    year = {1984},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_19125.shtml},
}