Mahabharata 13.87.6

अन्वाहार्यं महाराज पितॄणां श्राद्धमुच्यतेतच्चामिषेण विधिना विधिः प्रथमकल्पितः

anvāhāryaṃ mahārāja pitṝṇāṃ śrāddhamucyatetaccāmiṣeṇa vidhinā vidhiḥ prathamakalpitaḥ

Our plain-language meaning of this verse is waiting for scholar review.