RT Journal T1 THE EXISTENCE AND NON-EXISTENCE OF SIGN-CHANGING SOLUTIONS TO BI-HARMONIC EQUATIONS WITH A p-LAPLACIAN A1 王文清, 毛安民 PB 数学物理学报(英文版) FD 2022-04-25 YR 2022 JF Acta Mathematica Scientia JO 数学物理学报(英文版) VO 42 IS 2 SP 551 DO 10.1007/s10473-022-0209-6 K1 Bi-harmonic;sign-changing solution;Fountain theorem LK {http://121.43.60.238/sxwlxbB/CN/article/article_16670.shtml}