1641
It was not until the early 1970s that Cambridge Prof. Harry Whittington and two sharp graduate students began to publish a reinterpretation of the Burgess Shale .
 the early 1970s, Cambridge, Harry Whittington, two, the Burgess Shale
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: date, organization, person, geographical social political, national religious political, facility, cardinal, location, work of art, law, event, product, ordinal, percent, time, quantity, money, language 
Text: {0} 
Answer:
 the early 1970s, Cambridge, Harry Whittington, two, the Burgess Shale