TY  - RPRT
TI  - Mathematical methods of site selection for electronic message systems (EMS) 
AU  - Witzgall, Christoph
PY  - 1975
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS IR 75-737
DO  - 10.6028/NBS.IR.75-737
ER  -