that's not the good place to find out about xi xia.
if you are really interested in it, you can check out the following stuff:
new things:
西夏史论文集
中国古代民族文字协会第一次会议论文集 -- some articles about
西夏文字 and 番汉合时掌中珠
old things:
西夏史
西夏史长编
you can also find related stuff from:
范文正公文集
韩文？公文集 (forgot this 韩琦's 谥号)
that will be a long long list but I think the above should give you
enough now.
