TY  - JOUR 
T1  - ESTIMATION AND ANALYSIS OF PROTECTION LEVELS FOR PRECISE APPROACH AT RIO DE JANEIRO INTERNATIONAL AIRPORT USING REAL TIME σ<sub>VIG</sub> FOR EACH GPS AND GLONASS SATELLITE
JO  - Boletim de Ciências Geodésicas
A1  - Pereira, Vinícius Amadeu Stuani
A1  - Monico, João Francisco Galera
A1  - Camargo, Paulo de Oliveira
SN  - 1982-2170
UL  - 10.1590/s1982-21702021000s00010
VL  - 27 
Y1  - 2021
PB  - Brasil 
ER  -