أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ حَدَّثَنَا حَمَّادُ بْنُ مَسْعَدَةَ، قَالَ حَدَّثَنَا ابْنُ مَوْهَبٍ، عَنِ الْقَاسِمِ بْنِ مُحَمَّدٍ، قَالَ كَانَ لِعَائِشَةَ غُلاَمٌ وَجَارِيَةٌ قَالَتْ فَأَرَدْتُ أَنْ أُعْتِقَهُمَا فَذَكَرْتُ ذَلِكَ لِرَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ ‏"‏ ابْدَئِي بِالْغُلاَمِ قَبْلَ الْجَارِيَةِ ‏"‏ ‏.‏

It was narrated that Al-Qasim bin Muhammad said: "Aishah had a male slave and a female slave. She said: 'I wanted to set them free, and I mentioned that to the Messenger of Allah. He said: Start with the male slave before the female slave.'" Translation Not Available

Book Ref: Sunan An Nisai Book 27 Hadith 3446
Web Ref:  Sunan An Nisai Vol 4 Book 27 Hadith 3476