Sahih Muslim Book 18, Hadith Number 4279.

Chapter : Stray thing found by anyone.

Salama b. Kuhail reported: I heard Sowaid b. Ghafala say: I went out, and also Zaid b. Suhan and Salman b. Rabi’a for Jibad, and I found a whip and took it up. They said to me: Leave it. I said: No. but I will make announcement of it and if its owner comes (then I will return that), otherwise I will use it, and I refused them. When we returned from Jihad. by a good fortune for me, I performed Pilgrimage. I came to Medina and met Ubayy b. Ka’b, and related to him the affair of the whip and their opinion (the opinion of Zaid b. Suhan and Salman b. Rabi’a) about it (i.e. I should throw it). Thereupon he said: I found a money bag during the lifetime of Allah’s Messenger (may peace be upon him) which contained one hundred dinars. I came to him along with it, and he said: Make an announcement of it for one year; so I announced it, but did not find anyone who could (claim it after) recognising it. I again came to him and he said: Make announcement for one year. So I made announcement of it, but I found none who could recognise it. I came to him he said: Make announcement of it for one year. I made announcement of that but did not find one who could recognise it, whereupon he said: Preserve (in your mind) its number, its bag and its strap, and if its owner comes (then return that to him), otherwise make use of it. So I made use of that. I (Shu’ba) met him (Salama b. Kuhail) after this in Mecca, and he said: I do not know whether he said three years or one year.