LiW N,Cui B T.Necessary and sufficient conditions for oscillation of neutral delay parabolic differential equations[J].Appl Math Comput,2001,121:147ˉ153.
[10]
Deng Liˉhu,W angHongˉzhou,GeW eiˉgao.J Beijing Institute ofTechnology,2001,10(1):12ˉ16.
Yang Jun,Guan Xingˉping.Oscillation for systems of nonlinear neutral type parabolic partial functional differential equations [J].ApplMath JCU,1997,B12:165ˉ178.