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Beginning in 1947 research provided new evidence about the ocean floor , and in 1960 Bruce C. Heezen published the concept of mid-ocean ridges .
 person: Bruce C. Heezen
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: Bruce C. Heezen