Shiva Purana
वाचकोऽयमहं वाच्यो मंत्रोऽयं हि मदात्मकः । तदनुस्मरणं नित्यं ममानुस्मरणं भवेत् १७ ।
It is the indicator and I am the indicated. This mantra is identical with me. The repetition of this mantra is verily my repeated remembrance.
english translation
vAcako'yamahaM vAcyo maMtro'yaM hi madAtmakaH । tadanusmaraNaM nityaM mamAnusmaraNaM bhavet 17 ।
hk transliteration by Sanscript