Sunan an Nasai
4228
Sahih+2

It was narrated that Nubaishah said:"It was said to the prophet: 'During the Jahiliyyah we used to offer the 'Atirah.' He said: 'Slaughter for the sake of Allah, the Mighty and sublime, no matter what month it is; do good for the sake of Allah, the Mighty and sublime, and feed the poor

SahihAbu Ghuddah
SahihAl-Albani