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We don’t think President Donald Trump reads ProPublica Illinois. But, well, maybe he should.

On Wednesday, the president issued a pair of tweets warning about the media’s use of anonymous sources, claiming there aren’t actual people behind the information attributed to them.

Just a day earlier, as it happened, we posted a column on precisely this topic.

Trump, as many people know by now — and as many reporters quickly pointed out — was a frequent anonymous source for journalists before becoming president. He probably still is. Back when he was a real estate developer, Trump often leaked news and phony stories, frequently to promote himself or his businesses, according to reporters who covered the pre-White House Trump.

Often, he would use pseudonyms. One frequently used name in the ‘80s: John Baron. Another: John Miller. In many cases, Trump used fake names to boast to the tabloids about his (supposed) romantic exploits. He was even forced to admit at least once under oath that he had used fake names.

Despite all his personal experience as a not-so-anonymous anonymous source, Trump got it wrong. Reporters, in fact, go to great lengths to try to verify information they receive from unnamed sources. That’s what reporter Jason Grotto explained in our latest column about how we do our journalism.

One reader said the column was much-needed so readers can understand why sources receive anonymity. Another said it was “VERY important,” since misunderstandings about sourcing can lead to “unnecessary vitriol pointed at journalists.” And a third admitted that, before reading the column, she thought anonymous sources meant they were anonymous to even the reporter.

The need to better explain how journalism works is exactly why we started the “Ask ProPublica Illinois” column. So far this year, we’ve answered readers’ questions about how we prevent typos and other errors from getting in our stories, how we deal with sources and how we identify fake news — which seems particularly appropriate nowadays.

You can read the whole series. We’re still taking questions, too. Submit them to [email protected].