Can you give some references for this mudra...I can't seem to find the name anywhere? I like how it feels but just wanted to know where I can find more info.

I like this for me as a massage therapist. My hairstylist and piano teacher will enjoy this one in yoga class today! I'm teaching a new mudra every week and just found your mudra medicine wealth of knowledge! Yay!!!! Thank you so much for putting these videos together!
I too would love more history of it.