3110
His early work was in general topology , where he introduced Esenin-Volpin 's theorem .
 person: Esenin-Volpin
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Esenin-Volpin 
Answer:
 person: Esenin-Volpin