Letter to Mr Schwensen (24 july 1911)
From The Arthur Conan Doyle Encyclopedia
This letter was written by Arthur Conan Doyle on 24 july 1911 to (probably) Sir William Conyngham Greene (1854-1934) with whom Doyle had dinner with in Copenhagen the day before the wedding (on 2 august 1911) of Conan Doyle's brother, Major John Innes Doyle with Miss Clara Schwensen, daughter of Landowner Reinholdt Schwensen (Mr. Schwensen in the letter). 
July 24 / 11
Pray excuse the delay in answering your kind invitation. I am not clear whether Mr. Schwensen may have made some arrangement for us upon Tuesday. We are of course in his hands. If not we shall be happy to accept your invitation to dinner.
Yours very truly
Arthur Conan Doyle
- source: Bruun Rasmussen Kuntzauktioner