A PROOF OF HIGGINS'S CONJECTURE

摘要

Let Θ: G = ∏_(λ∈Λ) G_λ→B = ∏_(λ∈Λ) B_λ be a group homomorphism between free products of groups such that G_λΘ = B_λ for all λ∈Λ for all λ∈Λ. Let H is contained in G be a subgroup such that HΘ=B. Then H = ∏_(λ∈Λ)H_λ such that H_λΘ = B_λ and H_λ = ∏~*(H∩G_λ~(βλ,μ) * F_λ where F_λ is free.