contradiction in terms vs self-contradiction

contradiction in terms

noun
  • A phrase or expression in which the component words contradict one another, often unintentionally, or are claimed to do so when seen from a particular point of view. 

self-contradiction

noun
  • A statement that contains a contradiction, or a premise from which one could be derived 

How often have the words contradiction in terms and self-contradiction occurred in a corpus of books? (source: Google Ngram Viewer )