Shiva Purana
नंदिसंस्थानतः पश्चान्न विदुः शिववैभवम् । नंदीश्वरो बहिस्तिष्ठन्पंचाक्षरमुपासते ११८ ।
No one can realise the flourishing power of Śiva stationed at the back of Nandi. Nandīśvara sits outside and repeats the five-syllabled mantra.
english translation
naMdisaMsthAnataH pazcAnna viduH zivavaibhavam । naMdIzvaro bahistiSThanpaMcAkSaramupAsate 118 ।
hk transliteration by Sanscript