PageRank Split Experiment
Yes, it is worth to get links on a “links page” with many links if domain has high authority. via @mediadonis
Ethics in SEO: Your Website's Best Defense Against Google Algorithm Updates - Forbes
nice guest article ;-)
Why do paid links violate Google’s guidelines while other ads don’t? (by GoogleWebmasterHelp)
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Google has made it very clear that it wants links to be a sign of a real reason to link, an AUTHENTIC vote of confidence if you will. Anything that is paid for, is not considered quality by Google and participating in it puts your site at risk!