1. Interplanetary navigation using pulsating radio sources;Downs,1974
2. Navigation using x-ray pulsars;Chester,1981
3. Navigation Studies Utilizing the Nrl-801 Experiment and the Argos Satellite;Wood,1993
4. The unconventional stellar aspect (usa) experiment on argos;Kowalski,2001
5. The use of x-ray pulsars for spacecraft navigation;Sheikh,2004