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Swiss scientist Johann Heinrich Lambert in 1761 proved that π , the ratio of a circle 's area to its squared radius , is irrational , meaning it is not equal to the quotient of any two whole numbers .
 person: Johann Heinrich Lambert
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: Johann Heinrich Lambert 
Answer:
 person: Johann Heinrich Lambert