Shiva Purana
तदोंनमः शिवायेति श्रीशब्द पूर्वकाय च ॥ वारान्षोडश संकल्पपूजां कुर्यादयं बटुः॥ ४४ ॥
Then the brahmin boy performed the Saṃkalpapūjā (worship by mental conception) sixteen times with the five-syllabled mantra with the word Śrī prefixed to Śiva.
english translation
tadoMnamaH zivAyeti zrIzabda pUrvakAya ca ॥ vArAnSoDaza saMkalpapUjAM kuryAdayaM baTuH॥ 44 ॥
hk transliteration by Sanscript