Sahih Muslim Book 6, Hadith Number 2473.

Chapter : Permissibility of observing the fast or not observing it in the month of Ramadan for a traveller.

This Hadith has been narrated by Ja’far with the some chain of transmitters and he added: It was said to him (to the Holy Prophet): There are people to whom fasting has become unbearable and they are waiting how you do. He (the Holy Prophet) then called for a cup of water when it was afternoon. The rest of the Hadith is the same.