wangshirf 2010/09/18
1111111111111111111 [url]http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TGF-4429T2F-6&_user=10&_coverDate=11%2F30%2F1994&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1465116697&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=7b55cbceb3eca07bc4f7c4c926422daf&searchtype=a[/url]