It is in the Rules.
However, in such situations, the player may not, in a single procedure, concurrently take relief from two conditions by dropping a ball in a single relief area determined by a combined nearest point of complete relief from both conditions, except in the situation where the player has successively taken relief for interference from each condition and is essentially back where the player started.
I'll only ever leave a ball in the trap once.
I'm launching number two into the stratosphere. Some of the longest, most majestic shots I ever hit come out of the greenside bunker on the second effort..