Cabada A. The method of lower and upper solutions for second, third, fouth and higher order boundary value problems[J]. J Math Anal Appl,1994,185:302-320.
[2]
Kong L, Wang S, Wang J. Positive solution of a singular nonlinear third-order periodic boundary value problem [J]. J Comput Appl Math,2001,132:247-253.
[3]
Sun J, Liu Y. Multiple positive solutions of sigular third-order periodic boundary value problem [J]. Acta Math Sci,2005,25:81-88.
[4]
Feng Y. On the exixtence and multiplicity of positive periodic solutions of a nonlinear third-order equation[J]. Appl Math lett,2009,22:1220-1224.
[5]
Chu J, Zhou Z. Positive solutions for singular non-linear third order periodic boundary value problems[J]. Nonlinear Anal,2006,64:1528-1542.
[6]
Li Y. Positive periodic solutions for fully third-order ordinary differential equations [J]. Comput Appl Math,2010,59:3464-3471.
Li Y. Existence and uniqueness for higher order periodic boundary value problem under spetral separarion conditions[J]. J Math Anal Appl,2006,322:530-539.
[9]
Ren J L, Cheng Z B, Chen Y L. Existence results of periodic solutions for third order nonlinear sigular differential equation [J]. Math Nach,2013,286:1022-1042.
[10]
Cheng Z B. Exixtence of positive periodic solutions for third-order differential equation with strong singularity[J]. Adv Difference Equ,2014,162:1-12.
[11]
Cheng Z B, Ren J L. Existence of positive periodic solution for variable-coefficient third order differential equation with singularity[J]. Math Meth Appl Sci,2014,37:2281-2289.
Wang Y, Lian H, Ge W. Periodic solutions for a second order nonlinear funtional differential equation[J]. Appl Math Lett,2007,20:110-115.
[14]
Li Y H, Zhang X Y. Multiple positive solutions of boundary value problems for system of nonlinear third-order differential equations[J]. J Math Res Appl,2013,3:321-329.
[15]
Chen L, Hu L G, Ma X D. Positive solutions to singular eigenvale problems for third-order differential equations[J]. Acta Anal Funct Appl,2012,14:377-387.
[16]
Deimling K. Nonlinear Functional Analysis[M]. Berlin:Springer-Verlag,1985.