historians argue that china and tibet remained two separate units hi there are you sure that sentence which you added to amdo appears in the source cited the story of tibet conversations with the dalai lama by thomas laird grove press isbn i couldn't find it in there could you give me a pinpoint i e page reference the same sentence appears in history of tibet where it is tagged citation needed if you can give me a pinpoint citation for the sentence it should also be added to that article talk