Twin solutions to singular semipositone problems

In this paper, by a specially constructed cone and the fixed point index theory, we investigate the existence of multiple positive solutions for the following singular semipositone problem: {y" + lambdaf(t, y) = 0, t epsilon (0, 1)}, {y(0) = y(1) = 0}. The nonlinear term f(t, y) may be singular at t = 0, t = 1, and y = 0, also may be negative for some values of t and y; and lambda is a positive parameter. (C) 2003 Elsevier Inc. All rights reserved.