2083
One of the challenging problems of real algebraic geometry is the unsolved Hilbert 's sixteenth problem : Decide which respective positions are possible for the ovals of a nonsingular plane curve of degree 8 .
 person: Hilbert
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 person: Hilbert