Jami` at-Tirmidhi 25
جامع الترمذي#25HasanRabah bin Abdur-Rahman bin Abi Sufyan bin Huwaitib narrated from his grandmother, from her father; she said (that he said):"I heard Allah's Messenger saying: there is no Wudu for one who does not mention Allah's Name over it
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirHasan
Al-AlbaniHasan
Bashar Awad MaaroufHasan
Zubair Ali ZaiHasan
In-book reference: 1:25