1Hu. Wang. Multiple positive solutions of boundary value problems for systems of nonlinear second - order differential equations [J]. J. Math. Anal. App1,2007,335:1052 - 1060.
4M. A. Krasnosel' skii, Positive Solutions of Operator Equations [M]. Groningen : Noordhoff, 1964.
5Anderson D., Davis J. M. Multiple solutions and eigenvalues for third - order right focal boundary value problems [J]. J Math Anal Appl, 2002, 267:135 -157.
8Z. T. Zhang. Existence of non - trivial solution for superlinear system of integral equations and its applications [J]. Acta Math. Sinica ( in Chinese), 1999 ( 15 ) : 153 - 162.
