60602
In 1973 , Richard Greenblatt and Thomas Knight , and eventually to 40-bits or more ( usually , the excess bits not accounted for by the following were used for error-correcting codes ) .
 person: Richard Greenblatt; person: Thomas Knight
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: Richard Greenblatt, Thomas Knight 
Answer:
 person: Richard Greenblatt; person: Thomas Knight