1. Beardon, A.F., Minda, D.: The hyperbolic metric and geometric function theory. In: Ponnusamy, S., Sugawa, T., Vuorinen, M. (eds.) Quasiconformal Mappings And Their Applications, pp. 9–56. Narosa Publishing House, New Delhi (2007)
2. Cao J., Zhang X.: Constructions of strongly hyperbolic spaces, Manuscript. (2022), 9 pp
3. Chen, J., Hariri, P., Klén, R., Vuorinen, M.: Lipschitz conditions, triangular ratio metric, and quasiconformal maps. Ann. Acad. Sci. Fenn. Math. 40, 683–709 (2015)
4. Hariri, P., Klén, R., Vuorinen, M.: Local convexity of metric balls. Monatsh. Math. 186, 281–298 (2018)
5. Hariri, P., Klén, R., Vuorinen, M., Zhang, X.: Some remarks on the Cassinian metric. Publ. Math. Debrecen. 90, 269–285 (2017)