If you are paying attention to the subject of the article and most of the comments on this page, you should have no trouble generating one yourself. Just search for anything involving basic html or css, like, say "html title tag", and see that the first result, and often the first three results, are to an inferior site (w3schools) sporting Adsense ads. Then there are some more like that. The high quality results (w3.org, mdn) start halfway down. None of these have any advertising, and so they generate no revenue for Google.