Gaya APA
ICAO, . (1953).
CIRCULAR 33-AN/28 CONTROL OF IFR AIR TRAFFIC ALONG AIRWAYS USING FLIGHT PROGRESS BOARD .
Canada:
ICAO.
Gaya MLA
ICAO, .
"CIRCULAR 33-AN/28 CONTROL OF IFR AIR TRAFFIC ALONG AIRWAYS USING FLIGHT PROGRESS BOARD".
Canada:
ICAO,
1953.
Text.