Sunan Abu Dawud
177
Sahih+3

Abu Hurairah said:The Messenger of Allah (ﷺ) said: If any one of you offers prayer and feels a movement between his paddocks, but is doubtful whether or not his ablution broke, he should not cease praying unless he hears a sound or perceives a smell

SahihAl-Albani
SahihMuhammad Muhyi Al-Din Abdul Hamid