Absolutely. You could even add fake citations to online newspapers – the odds of someone checking are very low, and I continually stumble upon either blatant fabrications or misunderstandings that have stood there "sourced" for years on high-traffic articles.
Just create a citation loop and create facts from nowhere!
Even better: I remember there being a Wikipedia edit on some German person's name, that was copied by a newspaper and then that name in the newspaper was cited as a justification to not fix the name back. It might be https://en.wikipedia.org/wiki/Karl-Theodor_zu_Guttenberg, but I can't find any references about Wikipedia not correcting the name.