1. Aleksandrov, A.D., Zalgaller, V.A.: Two-dimensional manifolds of bounded curvature. (Foundations of the intrinsic geometry of surfaces.). Trudy Mat. Inst. Steklov 63, 262 (1962)
2. Burago, D., Burago, Y., Ivanov, S.: A Course in Metric Geometry. Graduate Studies in Mathematics, vol. 33. American Mathematical Society, Providence (2001)
3. Bergweiler,W., Eremenko, A., Langley, J.: On Conformal Metrics of Constant Positive Curvature in the Plane. arXiv:2208.04672, (2022)
4. Bonk, M., Kleiner, B.: Quasisymmetric parametrizations of two-dimensional metric spheres. Invent. Math. 150(1), 127–183 (2002)
5. Berestovskij, V.N., Nikolaev, I.G.: Multidimensional generalized Riemannian spaces. In: Geometry, IV, volume of Encyclopaedia Math. Sci., vol. 70, pp. 165–243, 245–250 (Springer, Berlin, 1993)