‏الصلاة : Hadeeth No:1920 Salim narrated on the authority of his father that the Prophet of Allaah (sallAllaahu alayhi wa sallam) used to observe two rak'ahs after Jumu'a....

‏الجهاد والسير‏ : Hadeeth No:4362 The same tradition has been narrated by a different chain of transmitters with a slight difference in the wording....