Historical Rules · 13 November 2015
Rule 500.7
Official source text from the 13 November 2015 Rules release
Some effects can give a player extra turns. They do this by adding the turns directly after the current turn. If a player is given multiple extra turns, the extra turns are added one at a time. If multiple players are given extra turns, the extra turns are added one at a time, in APNAP order (see rule 101.4). The most recently created turn will be taken first.