We prove that the T-periodic extension of a convex function f1:[0;T[[0;+[f_{1}:[0;T[ \rightarrow [0;+\infty[, is n-subhomogeneous if and only if A=limx0+f1(x)nf1(kTn)andB=limxTf1(x)nf1(kTn)A = \lim_{x\to 0^{+}} f_{1}(x)\leq nf_{1}(k \frac{T}{n}) \quad \text{and} \quad B = \lim_{x\to T^{-}}f_{1}(x)\leq nf_{1}(k \frac{T}{n}) for every k=1,2,...,n1,(n2)k=1,2,...,n-1, (n\geq 2).

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C. Peppo. “A Note on n-Subhomogeneity of Periodic Extension of Convex Functions.” Journal of Convex Analysis 24 (2017), No. 1, 305–308.