I found two versions of the Agni Sara practice.

One is similiar to what Swami Rama seems to teach in a Youtube video, where you slowly draw in the abdomen on exhale and then slowly relax on exhale and repeat 100 times. (This is the version I'm looking for to practice).

The second one is what the majority of videos on Youtube of people teaching Agni Sara shows, which is to exhale, ans when the breath is totally out of the body you move your belly in and out very fast for as long as you can while retaining the breath out.(This is not the version I'm looking for because Swami Rama says in that video to not do it fast, so it's the first version I want).

Can someone help me find videos of the first version where people teach it on Youtube?

For some reason it seems to be very hard to find this first version of Agni Sara teaching.