bismarck vs jam doughnut

bismarck

noun
  • A jelly doughnut: a doughnut filled with jam and coated with sugar. 

  • A doughnut filled with cream, often with chocolate icing. 

  • A fried cruller, or a sort of pancake. 

jam doughnut

noun
  • A doughnut filled with jam and usually topped with sugar. 

How often have the words bismarck and jam doughnut occurred in a corpus of books? (source: Google Ngram Viewer )