Citing this Article

Owing to the fact that a Living Reviews article may evolve over time, we recommend to cite the article as follows:

J. W. Armstrong,
"Low-Frequency Gravitational Wave Searches
Using Spacecraft Doppler Tracking",
Living Rev. Relativity 9,  (2006),  1. URL (cited on <date>):

The date given as <date> then uniquely identifies the version of the article
you are referring to.