中国科学院数学与系统科学研究院期刊网
A Necessary and Sufficient Condtion for the Existence of Positive Solutions of Singular Superlinear Boundary Value Problems
Zhong Li WEI(1), Zhi Tao ZHANG
Acta Mathematica Sinica, Chinese Series . 2005, (1): 25 -34 .  DOI: 10.12386/A2005sxxb0004