Michael Wolff has tapes to back up quotes in his incendiary book — dozens of hours of them.

Among the sources he taped, I'm told, are Steve Bannon and former White House deputy chief of staff Katie Walsh.

So that's going to make it harder for officials to deny embarrassing or revealing quotes attributed to them in "Fire and Fury: Inside the Trump White House," out Tuesday.

to make it harder for officials to deny embarrassing or revealing quotes attributed to them in "Fire and Fury: Inside the Trump White House," out Tuesday. In some cases, the officials thought they were talking off the record. But what are they going to do now?

the officials thought they were talking off the record. But what are they going to do now? Although the White House yesterday portrayed Wolff as a poseur, he spent hours at a time in private areas of the West Wing, including the office of Reince Priebus when he was chief of staff.

yesterday portrayed Wolff as a poseur, he spent hours at a time in private areas of the West Wing, including the office of Reince Priebus when he was chief of staff. The White House says Wolff was cleared for access to the West Wing fewer than 20 times.

says Wolff was cleared for access to the West Wing fewer than 20 times. Wolff, a New Yorker, stayed at the Hay Adams Hotel when he came down to D.C., and White House sources frequently crossed Lafayette Park to meet him there.

Part of Wolff's lengthy index entry for Bannon:

Some reporters and officials are calling the book sloppy, and challenging specific passages.

How could Wolff possibly know for sure what Steve Bannon and the late Roger Ailes said at a private dinner?

possibly know for sure what Steve Bannon and the late Roger Ailes said at a private dinner? It turns out Wolff hosted the dinner for six at his Manhattan townhouse.

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