46971
Electoral systems with election of just one winner in each district ( i.e. , " winner-takes-all " electoral systems ) and no proportional distribution of extra mandates to smaller parties tend to create two-party systems ( Duverger 's law ) .
 Duverger
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Duverger