... Graef and E Thandapani, Oscillatory and asymptotic behavior of fourth order nonlinear delay difference equations, Fasc Math (2001), no 31, 23–36 J W Hooker and W T Patula, Growth and oscillation ... β According to Lemma 2.5, we may regard an asymptotically constant solution as a “minimal” solution, and an asymptotically Qn,N solution as a “maximal” solution Now, we present a necessary and ... J Yan and B Liu, Oscillatory and asymptotic behaviour of fourth order nonlinear difference equations, Acta Math Sinica (N.S.) 13 (1997), no 1, 105–115 B G Zhang and S S Cheng, On a class of nonlinear...