when this grant of authority is viewed in the light of its apparent interpretation by the trustees, together with the fact that petitioners presented no evidence to show that this power was in any way restricted, we believe that Richard, in conjunction with two nonadverse parties, could control and dispose of the beneficial interest of the entire trust corpus and income. See Gurich v. Commissioner, 295 F.2d 845 (1st Cir. 1961). We are cognizant of the fact that trustees are subject to certain duties and limitations imposed by local law.