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2. Finding the origin of the Pioneer anomaly
3. The early universe (Springer, Berlin, 2003).
4. The confrontation between general relativity and experiment. Living Rev. Relativity, 4, 4 (2001), cited on July 7, 2004.
5. Relativity in the global positioning system. Living Rev. Relativity, 6, 1 (2003), cited on July 7, 2004.