Abu Hurairah (RA) reported Allah's Messenger (ﷺ) as saying: The yawning as from the devil. So when one of you yawns he should try to restrain it as far as it lies in his power.
Hadith Referenceصحيح مسلم / كتاب الزهد والرقائق / 2994
The son of Abu Said al-Khudri reported on the authority of his father that Allah's Messenger (ﷺ) said: When one of you yawns, he should try to restrain it with the help of his hand since it is the Satan that enters therein.
Hadith Referenceصحيح مسلم / كتاب الزهد والرقائق / 2995