User-agent: linkwalker
Disallow: /

User-agent: TurnitinBot
Disallow: /        

User-agent: grub-client
Disallow: /

User-agent: Zao
Disallow: /        

User-agent: http://www.almaden.ibm.com/cs/crawler 
Disallow: /

User-agent: VoilaBot
Disallow: /

User-agent: *
Disallow: