“…. 7 Here and also in (3.20) uv stands for max ≤κ (u, v). This notation does not cause any inconsistency with the notation of Theorem 3.1/(A) since for any two positive idempotent elements u, v of an odd or even involutive FLe-chain (X, ≤, •, →, t, f ) it holds true that uv = max ≤ (u, v) which is further equal to max ≤κ (u, v) by (3.2).…”