Shiva Purana
पंचमुद्रा ः! प्रदर्श्याथ शिवमंत्रजपं चरेत् । शतरुद्रि यमंत्रेण जपेद्वेदविचक्षणः ३६ ।
After showing all these five Mudrās he shall perform the “Śiva Mantra[51] Japa”. The devotee well versed in the Vedas shall recite the “Śatarudriya” mantra.
english translation
paMcamudrA H! pradarzyAtha zivamaMtrajapaM caret । zatarudri yamaMtreNa japedvedavicakSaNaH 36 ।
hk transliteration by Sanscript