Jami At Tirmidhi
788
Sahih+3

Asim bin Laqit bin Sabrah narrated:From his father who said: "I said. 'O Messenger of Allah! Inform me about Wudu.' So he said: "Perform Wudu well, and go between the fingers, and perform Istinshaq extensively except when fasting

SahihAhmad Muhammad Shakir
SahihAl-Albani