Sunan an-Nasa'i, Volume 5, Book 43, Hadith 4366 (DarusSalam) ⓘ
It was narrated from Ummm Salamah that the Prophet said: "Whoever sees the new crescent of Dhul-Hijjah and wants to offer a sacrifice, let him not remove any of his hair or nails until he has offered the sacrifice."
أَخْبَرَنَا سُلَيْمَانُ بْنُ سَلْمٍ الْبَلْخِيُّ، قَالَ حَدَّثَنَا النَّضْرُ، - وَهُوَ ابْنُ شُمَيْلٍ - قَالَ أَنْبَأَنَا شُعْبَةُ، عَنْ مَالِكِ بْنِ أَنَسٍ، عَنِ ابْنِ مُسْلِمٍ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ، عَنْ أُمِّ سَلَمَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " مَنْ رَأَى هِلاَلَ ذِي الْحِجَّةِ فَأَرَادَ أَنْ يُضَحِّيَ فَلاَ يَأْخُذْ مِنْ شَعْرِهِ وَلاَ مِنْ أَظْفَارِهِ حَتَّى يُضَحِّيَ " .
also referenced under: Hadith 4361 (Reference) & Book 43, Hadith 1 (In-Book)