“…Result (2) was proved by Hadamard in 1893 [6] and is celebrated in the literature as the Hermite-Hadamard integral inequality for convex functions [2]. Along the years, it has been extended to different classes of convex functions: see, e.g., [3,8,15] and references therein. In 2016, the so called ϕ-convexity was introduced [5], subsequently denoted as η-convexity [4,12].…”