go-slow vs work-to-rule

go-slow

noun
  • Deliberate slow working as a protest during an industrial dispute. 

  • A period of time spent in an unusually slow fashion. 

work-to-rule

noun
  • A labor protest in which employees do only the minimum work required by the rules of a workplace, following safety or other regulations to the letter in order to cause a slowdown. 

adj
  • Of or pertaining to such a protest. 

How often have the words go-slow and work-to-rule occurred in a corpus of books? (source: Google Ngram Viewer )