“…They are based on a modification of the Yang-Baxter equation, nowadays called the dynamical Yang-Baxter equation, see (1.2) below, which had previously been found by Gervais and Neveu in their study of the exchange relations of vertex operators in the Liouville conformal field theory [26]. The dynamical Yang-Baxter equation reappeared in various contexts since, e.g., [1,9,10,14,15,29,32,42,43]. A recent textbook on elliptic quantum groups is [36].…”