Sir Arthur Conan Doyle described how he was commissioned to write the story over a dinner with Joseph M. Stoddart, managing editor of an American publication Lippincott's Monthly Magazine, at the Langham Hotel in London on 30 August 1889.
Sir Arthur Conan Doyle a descris cum a fost însărcinat să scrie acest roman cu prilejul unui dineu literar organizat de Joseph M. Stoddart, directorul editorial al revistei Lippincott's Monthly Magazine, la Hotelul Langham din Londra, în 30 august 1889.