Shiva Purana
शिवोहमस्मीति सदा समाधिस्थो भवेति तम् ॥ सम्प्रोच्याथ स्वयं तस्मै नमस्कारं समाचरेत् ॥ ४९ ॥
He should always be in samadhi saying 'I am Shiva' Then one should offer obeisances to him himself.
english translation
zivohamasmIti sadA samAdhistho bhaveti tam ॥ samprocyAtha svayaM tasmai namaskAraM samAcaret ॥ 49 ॥
hk transliteration by Sanscript