Bulugh al-Maram, Book 3, Hadith 596 (English)

Umm ‘Atiyah (RAA) narrated, ‘We were forbidden to accompany funeral processions, but this prohibition was not mandatory for us.’ Agreed upon.

وَعَنْ أُمِّ عَطِيَّةَ رَضِيَ اللَّهُ عَنْهَا قَالَتْ: { نُهِينَا عَنِ اتِّبَاعِ الْجَنَائِزِ, وَلَمْ يُعْزَمْ عَلَيْنَا } مُتَّفَقٌ عَلَيْه ِ 1‏.‏ ‏1 ‏- صحيح.‏ رواه البخاري (1287)‏، ومسلم (938)‏، وانظر "ناسخ الحديث" (314)‏.‏

sunnah.com

also referenced under: Book 3, Hadith 40 (In-Book)