Yahya related to me from Malik from Abdullah ibn Yazid al-Madaniand from Abu'n Nadr from Abu Salama ibn Abd ar-Rahman from A'isha, thewife of the Prophet, may Allah bless him and grant him peace, that theMessenger of Allah, may Allah bless him and grant him peace, used topray sitting. He would recite sitting, and then, when about thirty orforty ayats of what he was reciting remained, he would stand up andrecite standing and then go into ruku and sajda. He would do the samein the second raka.
App reference: Book 8, Hadith 24
USC-MSA web (English) reference: Book 8, Hadith 24
Arabic reference: Book 8, Hadith 313