1747
The logistic function was introduced in a series of three papers by Pierre François Verhulst between 1838 and 1847 , who devised it as a model of population growth by adjusting the exponential growth model , under the guidance of Adolphe Quetelet .
 person: Pierre François Verhulst; person: Adolphe Quetelet
Please list all entity words in the text that fit the category.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} 
Answer:
 person: Pierre François Verhulst; person: Adolphe Quetelet