cicerone vs tour guide

cicerone

noun
  • A guide who accompanies visitors and sightseers to museums, galleries, etc., and explains matters of archaeological, antiquarian, historic or artistic interest.. 

tour guide

noun
  • A person who provides assistance and information to people on organised tours. 

How often have the words cicerone and tour guide occurred in a corpus of books? (source: Google Ngram Viewer )