(4) باب الإِبْرَادِ بِالظُّهْرِ فِي شِدَّةِ الْحَرِّ
It was narrated that Ibn 'Umar said:
"The Messenger of Allah said: 'Wait for it to cool down before you pray the Zuhr.'"
Reference: Sunan Ibn Majah 681
In-book reference: Book 2, Hadith 15
English translation: Vol. 1, Book 2, Hadith 681