Maliks Muwatta Book 20, Hadith Number 213.

Section : The Prayer of the Visitor of Makka or Mina.

Yahya related to me that Malik said, “Someone who comes to Makka at or before the new moon of Dhu’l-Hij ja and goes into ihram for the hajj should do the full prayer until he leaves Makka for Mina, and then he should shorten the prayer. This is because he has decided to stay there for more than four nights.”