"The prayer of the resident was enjoined on the tongue of your Prophet (ﷺ), four (rak'ahs), and the prayer of the traveler is two rak'ahs, and the prayer of fear is one rak'ah."
Sunan an-Nasa'i Book 15, Hadith 9
← Previous Hadith "The prayer for jumu'ah is two rak'ahs, and for Al-Fitr is two rak'ahs, and for An-Nahr is two rak'ahs, and for traveling is two rak'ahs, complete and not shortened, on the tongue of the Prophet (ﷺ)."

Sunan an-Nasa'i Book 15, Hadith 8 Next Hadith → "Allah, the Mighty and Sublime, enjoined the prayer on the tongue of your Prophet (ﷺ): While a resident four (rak'ahs), while traveling two, and at times of fear one."

Sunan an-Nasa'i Book 15, Hadith 10