Amāvasyā-Pitṛtarpaṇa: Purūravas and the Soma-Based Ancestral Offering (अमावस्या-पितृतर्पण / सोमतर्पण-विधि)
पूर्णामावस्ययोर्भेदौ ग्रन्थयः संधयश्च वै / अर्द्धमासं तु पर्वाणि द्वितीयाप्रभृतीनि तु
pūrṇāmāvasyayorbhedau granthayaḥ saṃdhayaśca vai / arddhamāsaṃ tu parvāṇi dvitīyāprabhṛtīni tu
The distinction between full moon and new moon is truly the knot and the junction; and the parvas of a half-month are the tithis beginning with the second day (Dvitīyā).