Sahih al Bukhari
1132

Narrated Masruq:I asked `Aisha which deed was most loved by the Prophet. She said, "A deed done continuously." I further asked, "When did he used to get up (in the night for the prayer)." She said, "He used to get up on hearing the crowing of a cock

1132.2

Narrated Al-Ashath:He (the Prophet (ﷺ) ) used to get up for the prayer on hearing the crowing of a cock