Asiatic buffalo vs water buffalo

Asiatic buffalo

water buffalo

noun
  • A water tank mounted on a trailer to be towed by a motor vehicle. 

  • A large ungulate, widely used as a domestic animal in Asia, South America. North Africa and Europe: Bubalus bubalis. 

How often have the words Asiatic buffalo and water buffalo occurred in a corpus of books? (source: Google Ngram Viewer )