Narrated Ibn 'Umar:
that the Prophet (ﷺ) said: "And at the setting of the stars (52:49) (about) the two Rak'ah before Fajr. And after the prostrations (50:40) 'The two Rak'at after Al-Maghrib.'" (RU)
English reference (RU): Vol. 5, Book 44, Hadith 3275 (RU)
Arabic reference (RU): Book 47, Hadith 3586 (RU)