Al-Kāfi - Volume 1 > Tacit and Explicit Testimony as proof of Ali ibn al-Husayn’s (a.s.) Divine Authority over the people after al-Husayn (a.s.)
Hadith #3

3ـ عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنْ عَلِيِّ بْنِ الْحَكَمِ عَنْ سَيْفِ بْنِ عَمِيرَةَ عَنْ أَبِي بَكْرٍ الْحَضْرَمِيِّ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ السَّلام) قَالَ إِنَّ الْحُسَيْنَ صَلَوَاتُ الله عَلَيْهِ لَمَّا صَارَ إِلَى الْعِرَاقِ اسْتَوْدَعَ أُمَّ سَلَمَةَ رَضِيَ الله عَنْهَا الْكُتُبَ وَالْوَصِيَّةَ فَلَمَّا رَجَعَ عَلِيُّ بن الحسين (عَلَيْهما السَّلام) دَفَعَتْهَا إِلَيْهِ.

3. A number of our people has narrated from Ahmad ibn Muhammad from Ali ibn al-Hakam from Sayf ibn ‘Amira from abu Bakr al-Hadrami from abu ‘Abdallah (a.s.) who has said the following. “When al-Husayn (a.s.) was about to leave for Iraq he entrusted ’Umm Salama (may Allah be pleased with her) with the books and directive will. When Ali ibn al-Husayn (a.s.) returned (to Madina) she delivered them to him. According to the manuscript of al-Safwan the hadith reads as follows: