blue book vs pop quiz

blue book

noun
  • A book of statistics or almanac, usually published by an agency or as a trade publication. 

  • Used other than figuratively or idiomatically: see blue, book. 

pop quiz

noun
  • A quiz or test given without warning or prior announcement. 

How often have the words blue book and pop quiz occurred in a corpus of books? (source: Google Ngram Viewer )