The book is based mainly upon printed sources, mostly books of traveler's recollections. The notes contain only four citations from manuscript collections, six from contemporary newspapers, and two from actual hotel registers. Of the numerous traveler's accounts used, a large proportion are those of foreigners, chiefly British. Since tourists, whether foreigners or easterners, would tend to remember and write about the most vivid episodes in their journeys, the use of many such sources probably explains the emphasis in the book on the bizarre and the extreme.