Owing to the fact that a Living Reviews in Relativity article may evolve over time, we recommend to cite the article as follows:
Carsten Gundlach and José M. Martín-García,
"Critical Phenomena in Gravitational Collapse",
Living Rev. Relativity 10, (2007), 5. URL (accessed <date>):
The date given as <date> then uniquely identifies the version of the article you are referring to.