Jami` at-Tirmidhi, Volume 5, Book 41, Hadith 2743 (DarusSalam) ⓘ
Narrated Iyas bin Salamah: from his father: "A man sneezed in the presence of the Messenger of Allah while I was present, so the Messenger of Allah said: 'Yarhamukallah (May Allah have mercy upon you).' Then he sneezed a second and third time. So the Messenger of Allah said: "This man is suffering from a cold.'"
حَدَّثَنَا سُوَيْدُ بْنُ نَصْرٍ، أَخْبَرَنَا عَبْدُ اللَّهِ، أَخْبَرَنَا عِكْرِمَةُ بْنُ عَمَّارٍ، عَنْ إِيَاسِ بْنِ سَلَمَةَ بْنِ الأَكْوَعِ، عَنْ أَبِيهِ، قَالَ عَطَسَ رَجُلٌ عِنْدَ رَسُولِ اللَّهِ صلى الله عليه وسلم وَأَنَا شَاهِدٌ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " يَرْحَمُكَ اللَّهُ " . ثُمَّ عَطَسَ الثَّانِيَةَ وَالثَّالِثَةَ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " هَذَا رَجُلٌ مَزْكُومٌ " . قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ .
also referenced under: Hadith 2743 (Reference) & Book 43, Hadith 2964 (In-Book)