Sayyidah Aisha Siddiqa (may Allah be pleased with her) narrates: The Prophet Muhammad (peace and blessings be upon him) used to offer eleven rak‘ahs at night; this was his regular prayer. He would perform such a long prostration in it that it would last as long as it takes one of you to recite fifty verses. And he used to offer two rak‘ahs before Fajr, then he would lie down on his right side until the muezzin would come to call him for prayer.
Hadith Referenceصحیح ابن حبان / كتاب الصلاة / 2614
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح: ق - انظر (2603). تنبيه!! رقم (2603) = (2612) من «طبعة المؤسسة». - مدخل بيانات الشاملة -.فضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده قوي