Electronic Journal of Differential Equations, Vol. 1999(1999), No. 34, pp. 1-8. Title: Positive solutions for a nonlinear three-point boundary-value problem Author: Ruyun Ma (Northwest Normal Univ. Gansu, China) Abstract: We study the existence of positive solutions to the boundary-value problem $$ \displaylines u''+a(t)f(u)=0,\quad t\in (0,1) \cr u(0)=0,\quad\alpha u(\eta)=u(1)\,, \cr} $$ where $0<\eta<1$ and $0<\alpha<1/\eta$. We show the existence of at least one positive solution if $f$ is either superlinear or sublinear by applying the fixed point theorem in cones. Submitted June 9, 1999. Published September 15, 1999. Math Subject Classifications: 34B15 Key Words: Second-order multi-point BVP; positive solution; cone; fixed point.