[ 1 ] GromovM. Hyperbolic groups [ M ]∥ Gersten S M. Essays in Group Theory. New York: Springer, 1987: 75 - 263. [2]BonkM, Heinonen J, Koskela P. Uniformizing Gromov Hyperbolic Spaces[M]. Asterisque Soci t Mathmatique de France, 2001, 270.Paris: Société Mathématique de France, 2001. [3]BuyaloS, Schroeder V. Elements of Asymptotic Geometry[M]. Berlin: EMS Press, 2007. [4]V is l J. Gromov hyperbolic spaces[J]. Expositiones Mathematicae, 2005, 23(3): 187-231. [5]ZhouQ S, Li Y X, Li X N. Sphericalizations and applications in Gromov hyperbolic spaces[J]. Journal of Mathematical Analysis and Applications, 2022, 509(1): 125948. [6]BessonG, Courtois G. Compactness and Finiteness Results for Gromov-Hyperbolic Spaces[M]. Cham: Springer, 2022.Compactness and finiteness results for Gromov-hyperbolic spaces[M]//Papadopoulos A. Surveys in Geometry I. Cham: Springer, 2022: 205-268. [7]BeardonA F, Minda D. The hyperbolic metric and geometric function theory[M]∥Ponnusamy S, Sugawa T, Vuorinen M. Quasiconformal Mappings and Their Applications. New Delhi: Narosa, 2007: 9-56. [8]KlnR, Lindn H, Vuorinen M, et al. The visual angle metric and Mbius transformations[J]. Computational Methods and Function Theory, 2014, 14(2): 577-608. [9]KlnR, Vuorinen M, Zhang X H. Quasihyperbolic metric and Mbius transformations[J]. Proceedings of the American Mathematical Society, 2014, 142(1): 311-322. [10]VuorinenM, Zhang X H. Distortion of quasiconformal mappings with identity boundary values[J]. Journal of the London Mathematical Society, 2014, 90(3): 637-653.