Shiva Purana
तां रुद्र संहितां यस्तु सपठेद्वटबिल्वयोः । प्रदक्षिणां प्रकुर्वाणो ब्रह्महत्या निवर्तते ३६ ।
If a slayer of brahmin circumambulates the trees of Vaṭa and Bilva reciting the verses from Rudrasaṃhitā he will become purified of the sin of Brahmin-slaughter.
english translation
tAM rudra saMhitAM yastu sapaThedvaTabilvayoH । pradakSiNAM prakurvANo brahmahatyA nivartate 36 ।
hk transliteration by Sanscript