SIMIĆ, Slavko; VUORINEN, Matti; WANG, Gendi. Sharp Lipschitz Constants for the Distance Ratio Metric. Mathematica Scandinavica, Berkeley, CA, United States, v. 116, n. 1, p. 86–103, 2015. DOI: 10.7146/math.scand.a-20452. Disponível em: https://journals.msp.org/mscand/article/view/398. Acesso em: 24 jul. 2026.