Hanafi
The sources give no view for it here.
عتق الرقبة الصغيرة
هل يُجزئ عتق الصغير في تحرير الرقبة؟
Each school’s answer
Hanafi
Not stated in the sources
Maliki
Not stated in the sources
Shafi'i
Not stated in the sources
Hanbali
Not stated in the sources
The texts
مسألة: يجزىء فيها الصغير، خلافا لمن منعه؛ لقوله تعالى: " فتحرير رقبة " فأطلق، ولأنها رقبة مؤمنة سليمة تامة الملك كالبالغ.
«الإشراف», al-Qadi Abd al-Wahhab p. 778
From the schools’ own books
Maliki
The sources give no view for it here.
Shafi'i
The sources give no view for it here.
Hanbali
The sources give no view for it here.
What bears this mark is in our words, our standard wording; the books’ texts stay as they are.