GD208/21 SOUTH CHINA SEA GEOLOGICAL SURVEY WORK BY M/V “HUI TONG 628” “SHUN HANG 168” “HUA HAI 258” IN AREA BOUNDED BY 21-12-50N 112-10-01E，21-05-38N 112-10-01E，21-05-38N 112-17-06E AND 21-12-50N 112-17-06E FROM 15 SEP. TO 30 NOV. SIGNAL LIGHTS AND SHAPES WILL BE EXHIBITED ADVISED TO AVOID GUANGDONG MSA CHINA