Let (X,∥.∥X)(X, \|.\|_X) be an order-continuous Banach ideal space over a σ-finite measure space (Ω, Σ, μ) and E a Banach space. We prove that a function f of the vector Banach ideal space X(E) is a denting point of the unit ball of X(E) if and only if: (i) the modulus function ∣f∣:t⟼∥f(t)∥|f|: t \longmapsto \|f(t)\| is a denting point of the unit ball of X and (ii) f(t)/∥f(t)∥f(t)/\|f(t)\| is a denting point of the unit ball of E for almost all t in supp(f). This gives an answer to the open problem raised in a paper of Castaing and Pluciennik

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H. Benabdellah

Dép. de Mathématiques, Faculté des Sciences, Semlalia, B.P. S15, Marrakech, Marocco

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H. Benabdellah. “Denting Points in Bochner Banach Ideal Spaces X(E).” Journal of Convex Analysis 6 (1999), No. 1, 183–194. https://doi.org/10.68381/jca06011