TY  - RPRT
TI  - Current concepts for a tracking and data relay satellite system.
AU  - Clark, G. Q.
AU  - Fellerman, K. D.
AU  - Schwartz, J. J.
PY  - 1972
UR  - https://ntrs.nasa.gov/citations/19730030620
ID  - 19730030620
ER  -