Under some conditions on f(u), we show that for λ small and Ω ⊂ ℝ3 convex, the only solution to the elliptic equation Δu − λu + f(u) = 0 in Ω, with u > 0 in Ω and ∂u∕∂ν = 0 on ∂Ω, is constant.
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