international rules football vs volleyball

international rules football

noun
  • A sport created as a mixture of Australian rules football and Gaelic football, to allow international matches between Australia and Ireland. 

volleyball

noun
  • A game played on a rectangular court between two teams of two to six players which involves striking a ball back and forth over a net. 

  • The inflated ball used in such a game. 

How often have the words international rules football and volleyball occurred in a corpus of books? (source: Google Ngram Viewer )