中国科学院数学与系统科学研究院期刊网
AMS
Oscillation of Second Order Nonlinear Delay Damped Difference Equations
S. H. SAKER, B. G. ZHANG
Acta Mathematica Sinica . 2007, (4): 715 -722 .  DOI: 10.1007/s10114-005-0792-1