[1]Gilbarg D, Trudinger N S. Elliptic Partial Differential Equations of Second Order. New York: Spinger\|Verlag, 1983
[2]Noussair E S, Swanson C A. Oscillation of semilinear elliptic inequalities by Riccati transformation. Canad J Math,1980,32(4): 908-923
[3]Wintner A. A criterion of oscillatory stability. Quart J Appl Math, 1948 ,11(7): 115-117
[4]Swanson C A. Semilinear second order elliptic oscillation.Canad Math Bull, 1979, 22(2):139-157
[5]Xu Z T, Ma D K, Jia B J. Oscillation for a class of elliptic differential equations of second order. Math Appl, 2003,16(1):42-48(in Chinese)
[6]Philos Ch G. Oscillation theorems for linear differential equations of second order. Arch Math, 1989, 53:483-492
[7]Kong Q. Interval criteria for oscillation of second order linear ordinary diffential equations. J Math Anal Appl, 1999, 229(1) :258-270
[8]Kamenev I V. An integral criterion for oscillation of linear differential equations. Math Zamtki, 1978, 23(2): 249-251(in Russian) |