Michael Wolff note says he doesn't know if Trump book is all true - Business Insider Deutschland

http://www.businessinsider.de/michael-wolff-note-says-he-doesnt-know-if-trump-book-is-all-true-2018-1?r=US&IR=T

An author's note at the start of 'Fire and Fury: Inside the Trump White House' makes clear Michael Wolff was not completely able to substantiate his account.