Brihat Samhita
गौरासितक्षितिभवं सम्पूज्य यथाविधि द्विजः पूर्वम् । विजने समेत्य रात्रौ स्पृष्ट्वा ब्रूयादिमं मन्त्रम् ॥ ४३-१६ ॥
The brāhmaṇa first worshiped Gaurasita Kṣitibhava in accordance with the prescribed rituals. At night one should meet in a deserted place and touch the body and chant the following mantra.
english translation
gaurAsitakSitibhavaM sampUjya yathAvidhi dvijaH pUrvam । vijane sametya rAtrau spRSTvA brUyAdimaM mantram ॥ 43-16 ॥
hk transliteration by Sanscript