wangshirf 2010/08/21
44444444444444444444 [url]http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6THN-4WNGW74-1&_user=10&_coverDate=09%2F30%2F2009&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1437416319&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=a4f573fd0590c8c80c8c5bb0541b2f33[/url]