=参考资料=
[[http://baike.baidu.com/linkurl=3PH4iN45QNd62aTfdyAEjCj4kKYAObRlt_YYTx6ybt_m1QDOjZD5Tr72u7a3C0RjGaBz2Ew1LrLPJkMfzjSkBdYU7XX5Pho2tDG1yx2prS_信息检索3PH4iN45QNd62aTfdyAEjCj4kKYAObRlt_YYTx6ybt_m1QDOjZD5Tr72u7a3C0RjGaBz2Ew1LrLPJkMfzjSkBdYU7XX5Pho2tDG1yx2prS]]
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