42222
Colchicum ritchii " was named by Robert Brown after Joseph Ritchie who he said was the first to observe the plant near Tripoli .
 Robert Brown, Joseph Ritchie, Tripoli
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 Robert Brown, Joseph Ritchie, Tripoli