string(240) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%A6%82%E4%BD%95%E7%BB%99%E8%AE%BA%E6%96%87%E6%A0%87%E5%BC%95%E7%94%A8 => Failed to connect to 101.89.117.144 port 38017: Connection refused"
如何给论文标引用
