Hammad bin Zayd حماد بن زيد بن درهم الأزدي الأزرق · The Book of the Times (of Prayer)

"Whoever catches up with a prostration of Subh before the sun rises, then he has caught up with it; and whoever catches up with a prostration of 'Asr before the sun sets, then he has caught up with it."

"The Messenger of Allah (ﷺ) said: 'Whoever forgets a prayer, let him pray it when he remembers it, for Allah says: "and perform prayer when you remember (li dhikra).'" I said to Az-Zuhri: "Is that how the Messenger of Allah (ﷺ) recited it?" He said: "Yes."