Shiva Purana
अश्वमेधगणाच्छ्रेष्ठं देवि चित्तप्रसाधनम् ॥ मुक्तिदं च तथा ह्येतद्दुष्प्राप्यं विषयैषिणाम् ॥ ३४ ॥
O goddess, disciplining of the mind is far more excellent than many a horse-sacrifice. It is conducive to salvation. It is inaccessible to those who adhere to sensual objects.
english translation
azvamedhagaNAcchreSThaM devi cittaprasAdhanam ॥ muktidaM ca tathA hyetadduSprApyaM viSayaiSiNAm ॥ 34 ॥
hk transliteration by Sanscript