中国科学院数学与系统科学研究院期刊网
NON-ISOSPECTRAL FLOWS, SYMMETRIES AND LIE ALGEBRA ASSOCIATED WITH THE SECOND-ORDER POLYNOMIAL SPECTRAL PROBLEM
CHEN DENGYUAN, ZENG YUNBO
Acta Mathematicae Applicatae Sinica . 1994, (2): 300 -307 .  DOI: 10.12387/C1994029