An oscillation criterion for a delay difference equation

By using the method of Yu, Zhang and Qian in [J.S. Yu, B.G. Zhang, X.Z. Qian, Oscillation of delay difference equations with oscillating coefficients, J. Math. Anal. Appl. 177 (1993) 432–444], we prove another oscillation criterion for all solutions of the following linear delay difference equation xn+1−xn+pnxn−k=0,n=0,1,2,… where {pn}{pn} is a sequence of real numbers and kk is a positive integer.