中国科学院数学与系统科学研究院期刊网
OSCILLATION AND ASYMPTOTIC BEHAVIOR OF SOLUTIONS OF FIRST ORDER LINEAR FUNCTIONAL DIFFERENTIAL EQUATIONS WITH OSCILLATORY COEFFICIENTS
Chen Yong-shao
Acta Mathematicae Applicatae Sinica . 1989, (1): 96 -104 .  DOI: 10.12387/C1989011