In Dante’s original writings (cycles on pennies), and the T-nation article
It’s just called “rest pause”. Nowadays, the waters are somewhat muddied. For instance, CT would describe this as “double rest-pause” to distinguish from taking just the one rest before going for reps again.
This is the first time I’ve read someone call it triple rest-pause. I’m not entirely sure what OP is referring to.
And, everyone stating “breaths” is correct. Just referenced Cycles on Pennies to write this reply. The prescription in seconds is from other coaches.