TABARANI 3910:
from Abū Ayyūb —
[Machine] The Messenger of Allah ﷺ said, "Whoever fasts Ramadan and six days of Shawwal, it is as if he has fasted the whole year."
الطبراني ٣٩١٠:
عن ابو ايوب —
أَنَّ رَسُولَ اللهِ ﷺ قَالَ «مَنْ صَامَ رَمَضَانَ وَسِتًّا مِنْ شَوَّالٍ فَكَأَنَّمَا صَامَ السَّنَةَ»