How to capture the Sogou web spider entries from Web log file?

Here are some Web log file entries:127.0.0.1 - frank [10/May/2012:13:55:36 -0700] "GET /apache_pb.gif HTTP/1.0" 200 2326 "-" "Sogou web spider/4.0(+http://www.sogou.com/docs/help/webmasters.htm#07)" "-" 213.135.131.79 - - [13/May/2012:17:35:32 -0600] "POST /submit.jsp HTTP/1.0" 200 2326 "-" "msnbot-media/1.1 (+http://search.msn.com/msnbot.htm)" "SID=1000;LANG=EN" 213.135.131.79 - - [15/May/2012:19:21:49 -0400] "GET /features.htm HTTP/1.1" 200 9955 "http://www.abc.com/" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; Q312461)" "-"

Sogou Web Spider is a Web crawler from Sogou.com that obtains content for the Sogou Search engine. Sogou web spider uses the following user agent string:

Sogou web spider/4.0(+http://www.sogou.com/docs/help/webmasters.htm#07)

The regular expression to capture Sogou Web Spider entries from Apache Web log file can be written as: ^.*"(.*Baiduspider[^"]*)".*$ with the multiple lines modifier "m" specified: m