M. Broadie and J. Detemple, “The valuation of American options on multiple assets,” Mathematical Finance, 7, 241–285 (1997).
V. A. Vasin and V. V. Morozov, “Investment decisions under uncertainty and evaluation of American options,” International Journal of Mathematics. Game Theory and Algebra, 15, No. 3, 323–336 (2006).
K. V. Khizhnyak, “Evaluation of an infinite American call on maximum of risky and riskfree asset,” Vestnik MGU. Ser. 15: Vychisl. Mat. Kibern., No. 3, 23–30 (2011).
A. N. Shiryaev, Foundations of Stochastic Mathematical Finance, Vol. 2, Facts. Models, Vol. 3, Theory [in Russian], FAZIS, Moscow (1998).
H. U. Gerber and E. S. W. Shiu, “Martingale approach to pricing American options,” AUSTIN Bull., 24, 195–200 (1994).
V. V. Morozov and D. L. Muravei, “A lower bound on the value of an infinite American call option on two assets,” Prikl. Matem. Informat., MGU, MAKS Press, Moscow, No. 36, 99–206 (2010).