Volume 6, Book 60, Number 489:
Narrated Abu Ubaida:
I asked ‘Aisha ‘regarding the verse:–‘Verily we have granted you the Kauthar.’ She replied, “The
Kauthar is a river which has been given to your Prophet on the banks of which there are (tents of)
hollow pearls and its utensils are as numberless as the stars.”