ICAO okays standards to kickstart aviation emissions accord. IN Shipping Bulletin. Manila Bulletin.
Chicago-viite (17. p.)"ICAO Okays Standards to Kickstart Aviation Emissions Accord. IN Shipping Bulletin." Manila Bulletin .
MLA-viite (9. p.)"ICAO Okays Standards to Kickstart Aviation Emissions Accord. IN Shipping Bulletin." Manila Bulletin, .
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