It is narrated from Ibn Abbas (may Allah be pleased with him) that he said: The Messenger of Allah (peace and blessings be upon him) was lowered into the blessed grave from the side of the head.
Hadith Referenceمسند الإمام الشافعي / كتاب الجنائز / 600
Hadith Takhrijاسناده ضعيف الجهالة الثقة وعمر بن عطاء ضعيف : اخرجه البيهقي : 4 / 54 ۔ وفى المعرفة السنن والآثار له (2177)۔