It is narrated from Ibn Abbas (may Allah be pleased with them) that the Prophet (ﷺ) was commanded to prostrate on seven parts: both hands, both knees, the sides of the toes (of the feet), and the forehead, and he was forbidden from gathering his hair and clothes. Ibn Tawus narrated additional words: that he placed his hand on the forehead and nose. (Ibn Tawus says) My father used to count the nose and forehead as one.
Hadith Referenceمسند الإمام الشافعي / كتاب الصلاة / 239
Hadith Takhrijأخرجه البخارى: الأذان، باب السجود على سبعة اعظم: 809، 810 ، 815- ومسلم، الصلاة، باب أعضاء السجود والنهي عن كف الشعر والثوب وعقص الرأس في الصلاة 490۔