TABARANI 19389:
from Hishām b. ʿUrwah from his father —
[Machine] "Khadijah passed away before the Prophet ﷺ migrated to Medina by about three years or so. He then married Aisha soon after Khadijah's death and did not take another wife on top of Khadijah until she passed away."
الطبراني ١٩٣٨٩:
عن هشام بن عروه عن أبيه —
«تُوُفِّيَتْ خَدِيجَةُ قَبْلَ مَخْرَجِ النَّبِيِّ ﷺ إِلَى الْمَدِينَةِ بِثَلَاثِ سِنِينَ أَوْ نَحْوَ ذَلِكَ وَتَزَوَّجَ عَائِشَةَ قَرِيبًا مِنْ مَوْتِ خَدِيجَةَ وَلَمْ يَتَزَوَّجْ عَلَى خَدِيجَةَ حَتَّى مَاتَتْ»
hadithunlocked.com