It is narrated from Sayyidah Umm Salamah (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) used to recite verse by verse, separately: first he would recite "All praise is for Allah, the Lord of the worlds" and then pause, then he would recite "The Most Gracious, the Most Merciful" and then pause. Ibn Abi Mulaykah (may Allah have mercy on him) said that Sayyidah Umm Salamah (may Allah be pleased with her) used to read this word as "maliki yawm al-din" (without an alif). This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it.