The Book of Transactions (Kitab Al-Buyu`)
Muslim :: Book 10 : Hadith 3889
Jabir reported: We went from Mecca to Medina with Allah's Messenger (may peace be upon him) when my camel fell ill, and the rest of the hadith is the same. (But it in also narrated in it: ) He (the Holy Prophet) said to me: Sell your camel to me. I said: No, but it is yours. He said: No. (it can't be), but sell it to me. I said: No, but, Allah's Messenger, it is yours. He said: No, it can't be, but sell it to me. I said: Then give me an 'uqaya of gold for I owe that to a person and then it would be yours. He (the Holy Prophet) said: I take it (for an 'uqiya of gold) and you reach Medina on it. As I reached Medina, Allah's Messenger (may peace be upon him) said to Bilal: Give him an 'uqiya of gold and make some extra payment too. He (Jabir) said: He gave me an 'uqiya of gold and made an addition of a qirat. He (Jabir) said: The addition made by Allah's Messenger (may peace be upon him) was with me (as a sacred trust for belssing) and lay with me in a pocket until the people of Syria took it on the Day of Harra.