bona fide vs ex cathedra

bona fide

adj
  • In good faith; sincere; without deception or ulterior motive. 

  • Genuine; not counterfeit. 

adv
  • In good faith; genuinely, sincerely. 

ex cathedra

prep
  • With authority based on one's rank or office. 

How often have the words bona fide and ex cathedra occurred in a corpus of books? (source: Google Ngram Viewer )