How is the extra hour documented in the fall daylight saving time change on official stuff?

It is my understanding that in fall the clocks go from 1 to 2 normally and then at 2am they jump back to 1am again. So how does that get documented on official stuff so people understand which of the two 1am – 2am sequences are being described? Is one denoted with a * or something?

E.g. Air traffic control, time of birth/death, train schedules in places where trains run all night, time-based triggers and logs on servers, banking transactions, police reports, etc.