Daraqutni

Asim bin Damrah narrates: We said to Sayyiduna Ali (may Allah be pleased with him): Tell us a hadith about the voluntary prayers (nawafil) of the Prophet (peace and blessings be upon him). He replied: "Who has the strength to do that?" The narrator says: We submitted, tell us as much as you can, we will perform as much as we are able. So Sayyiduna Ali (may Allah be pleased with him) informed us: The Prophet (peace and blessings be upon him), after performing the (obligatory) prayer, would wait until the sun rose high and became as elevated in the east as it is in the west at the time of Asr, then the Prophet (peace and blessings be upon him) would perform two rak‘ahs, and between them he would send peace upon the angels, the noble prophets, and their follower believers and Muslims. Then after that, he would wait until the forenoon, when the sun would rise as high as it does in the east at the time of Zuhr, then he would perform four rak‘ahs, separating them in the same manner as before. Then he would wait until the sun declined, then he would perform four rak‘ahs and in them he would send peace upon the close angels, the noble prophets, and their follower believers and Muslims, then after the Zuhr prayer he would perform two rak‘ahs (sunnah) and separate them in the same way, then before it he would perform four rak‘ahs (sunnah) and separate them in the same way.

Asim bin Damrah narrates: We asked Sayyiduna Ali (may Allah be pleased with him) about the prayer of the Noble Prophet (peace and blessings be upon him), so he said: "Who has the strength for it?" We said: We do not have the strength (but please tell us about it), so Sayyiduna Ali (may Allah be pleased with him) informed us: The Noble Prophet (peace and blessings be upon him) would wait until the sun had moved away from its rising place as far as it moves away from its setting place at the time of Asr, at that time he would perform two rak'ahs of prayer. Then he would wait until the sun had moved away from its rising place as far as it moves away from its setting place (i.e., when the time of decline had come), at that time the Noble Prophet (peace and blessings be upon him) would perform four rak'ahs of Sunnah before the Zuhr prayer after the decline, after Zuhr he would perform two rak'ahs of Sunnah, and then he would again perform four rak'ahs before (the prayer).