‏السلام : Hadeeth No:5479 Ibn 'Umar reported Allaah's Messenger (sallAllaahu alayhi wa sallam) as saying: Fever is from the vehement Paging of the Hell-fire, so cool it with water....

‏الذكر والدعاء والتوبة والاستغفار‏ : Hadeeth No:6585 Ibn 'Abbas reported this hadith through another chain of transmitters with a sliglit variation of wording....