51841
The crystal detector was developed into a practical device for wireless telegraphy by Greenleaf Whittier Pickard , who invented a silicon crystal detector in 1903 and received a patent for it on November 20 , 1906 .
 person: Greenleaf Whittier Pickard
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
 Entities: Greenleaf Whittier Pickard 
Answer:
 person: Greenleaf Whittier Pickard