The Boothby citation by Boris Johnson is wrong. Boothby's own account is that Hitler greeted him by saying his own name (without 'Heil') and lifting his right arm, and Boothby responded in the same manner. When Boothby said 'Heil Boothby', it was in response to Hitler's secretary saying 'Heil Hitler'; he did not say this to Hitler himself, and ... More @Wikipedia
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