Shiva Purana
आवाहनादिकांश्चैव ह्युपचारान्प्रकल्प्य वै । विधिवत्षोडश प्रीत्या देवमानर्च शङ्करम् ॥ २२॥
He worshipped Śiva performing all the sixteen ancillary services like invocation etc. with devotion according to the rules obtaining.
english translation
AvAhanAdikAMzcaiva hyupacArAnprakalpya vai । vidhivatSoDaza prItyA devamAnarca zaGkaram ॥ 22॥
hk transliteration by Sanscript