The Standard Schedules Information Manual (SSIM) published by the

International Air Transport Association The International Air Transport Association (IATA ) is a trade association of the world's airlines founded in 1945. IATA has been described as a cartel since, in addition to setting technical standards for airlines, IATA also organized tariff ...

documents international airline standards and procedures for exchanging airline schedules and data on aircraft types, airports and terminals, and time zones.

References

Official page at IATA
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