Hadith 17:382
Ibn Numayr narrated to us, from Abdullah ibn Umar, from Nafi, from Ibn Umar, that he used to return the greeting (salam) exactly as it was said to him: "Peace be upon you" (as-salamu alaykum).
حدثنا بن نمير عن عبد الله بن عمر عن نافع عن بن عمر أنه كان يرد السلام كما يقال له السلام عليكم