Abbas bin Abdul-Muttalib reported,
I said, "Messenger of Allah, teach me something to ask Allah 
for."He replied, "Ask Allah for well-being."I waited for several days, then came back and said, "Messenger of Allah, teach me something to ask Allah for."He said to me, "Abbas, uncle of the Messenger of Allah, ask Allah for well-being in this world and the next."
Tirmidhi 3514
Sahihحدثنا أحمد بن منيع حدثنا عبيدة بن حميد عن يزيد بن أبي زياد عن عبد الله بن الحارث
عن العباس بن عبد المطلب قال
قلت يا رسول الله علمني شيئا أسأله الله عز وجل قال سل الله العافية فمكثت أياما ثم جئت فقلت يا رسول الله علمني شيئا أسأله الله فقال لي يا عباس يا عم رسول الله سل الله العافية في الدنيا والآخرة
No references are available.
[Sahih] Ahmad narrated it, 1/209, and Humaydi, no. 462, from the hadith of Yazid, and it is daif. It has a hasan corroborating witness in Tabarani, 10/330, 331, and Hakim graded it sahih, 1/529, according to the criterion of Bukhari, and Dhahabi agreed with him.