It is reported that ‘Abdullâh b. Al-Mubârak said, “I once borrowed a pen in Al-Shâm (Transjordan) and went to return it. But when I came back to Marwu (Eng. Merv , in Central Asia) I saw that I still had it, so I went back to Al-Shâm to return it to its owner.”
Al-Dhahabî, Siyar A’lâm Al-Nubalâ`, Vol. 8 p395.