Sunan Abi Dawud 400
سنن أبي داود#400SahihNarrated Abdullah ibn Mas'ud: The extent of the shadow when the Messenger of Allah prayed (the noon prayer) was three to five feet in summer and five to seven feet in winter
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiIsnaad Hasan
In-book reference: 2:10