中国科学院数学与系统科学研究院期刊网
ON THE EQUIVALENCE PROBLEM OF DIFFERENTIAL EQUATIONS AND DIFFERENCE-DIFFERENTIAL EQUATIONS IN THE THEORY OF STABILITY
秦元勋
Acta Mathematica Sinica, Chinese Series . 1958, (4): 457 -472 .  DOI: 10.12386/A1958sxxb0042