“…Let A 1 , A 3 and A 5 be the vertices of a regular triangle with unit side length, ie, |A 1 − A 3 | = |A 1 − A 5 | = |A 3 − A 5 | = 1. We define a family Ψ 1 of four suitable contractions (1) 1 , … , (1) 4 , with respect to the same ratio 1 3 (see Freiberg and Lancia 23 ). Let V (1)…”