Shiva Purana

siva.sh/siva-purana/vishweshwara-samhita/24/10

भस्मनोद्धूलनं चैव यथा तिर्यक्!त्रिपुंड्रकम् । प्रमादादपि मोक्षार्थी न त्यजेदिति विश्रुतिः 1.24.१० ।

sanskrit

Dusting with the holy ashes and smearing the Tripuṇḍra in horizontal parallel lines shall not be abandoned by those who seek salvation. Śruti lays down that they shall not get negligent.

english translation

bhasmanoddhUlanaM caiva yathA tiryak!tripuMDrakam | pramAdAdapi mokSArthI na tyajediti vizrutiH 1.24.10 |

hk transliteration by Sanscript