Georgian Mathematical Journal
For the nth order nonlinear differential equation y (n)(t)=f(y(t)), t [0,1], satisfying the multipoint conjugate boundary conditions, y (j)(ai) = 0,1 i k, 0 j n i - 1, 0 =a 1 a 2 a k = 1, and i=1 k n i =n, where f: [0, ) is continuous, growth condtions are imposed on f which yield the existence of at least three solutions that belong to a cone.
Davis, John M.; Eloe, Paul W.; and Henderson, Johnny, "Triple positive solutions for multipoint conjugate boundary value problems" (1999). Mathematics Faculty Publications. 109.