It wasnarrated that Wa'il bin Hujr said:
"I saw the Prophet (ﷺ)making a circle with his thumb and middle finger, and raising the onenext to it (the index finger), supplicating with it during theTashah-hud." (DE)
English reference (DE): Vol. 1, Book 5, Hadith 912 (DE)
Arabic reference (DE): Book 5, Hadith 965 (DE)