Hadith #2333 (Sunan Abi Dawud)
Book: Fasting (Kitab Al-Siyam)
Narrator(s): Abu Ishaq al-Sabay'ai' أبو إسحاق السبيعي عمرو بن عبد الله, Ibn Umm Maktum, Muhammad bin 'Abdullah bin Numayr محمد بن عبد الله بن نمير, Sulaiman bin Hayan al-Azdi سليمان بن حيان الأزدي
Grade: Sahih

That man and the people of his city should not fast as an atonement except that they know (for certain) that the people of a certain city of Muslims had fasted on Sunday. In that case they should keep fast as an atonement.

Source: https://parallelquran.com/hadith/sunan-abi-dawud-2333/

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Hadith #5207 (Sunan Abi Dawud)
Book: General Behavior (Kitab Al-Adab)
Narrator(s): Abu Bakr bin Abi Shayba أبو بكر بن أبي شيبة, Sulaiman bin Hayan al-Azdi سليمان بن حيان الأزدي, Tarayf bin Mujalad, Abu Tamayma طريف بن مجالد أبو تميمة الهجيمي
Grade: Sahih

The Companions of the prophet (ﷺ) said to the prophet (ﷺ): The people of the Book salute us. How should we reply to them? He said: say : the same to you.

Source: https://parallelquran.com/hadith/sunan-abi-dawud-5207/