family name vs nom de guerre

family name

noun
  • A given name common in a family, or already borne by someone in the family (in the context of naming someone in the family after that family member). 

  • A surname. 

nom de guerre

noun
  • Synonym of pseudonym. 

How often have the words family name and nom de guerre occurred in a corpus of books? (source: Google Ngram Viewer )