Sayyiduna Abdullah bin Zubair (may Allah be pleased with him) narrates: The Noble Prophet (peace and blessings be upon him) said: "Two rak‘ahs (Sunnah or Nafl) will be performed before every obligatory prayer." These are the words of the narrator named Ibn Dawud: The narrator named Isma‘il has reported the word "maftubah" in place of "maktoobah."
Hadith Referenceسنن الدارقطني / كتاب الصلاة / 1046
Hadith Takhrij«أخرجه ابن حبان فى ((صحيحه)) برقم: 2455، 2488، والدارقطني فى ((سننه)) برقم: 1046، والطبراني فى((الكبير)) برقم: 14899»