Shiva Purana
पूर्वैस्तिलयवैश्चाथ कमलैः पूजयेच्छिवम् ॥ बिल्वपत्रैर्विशेषेण पूजयेत्परमेश्वरम् ॥ ६२॥
The devotee shall worship lord Śiva particularly with the leaves of the Bilva tree.
english translation
pUrvaistilayavaizcAtha kamalaiH pUjayecchivam ॥ bilvapatrairvizeSeNa pUjayetparamezvaram ॥ 62॥
hk transliteration by Sanscript