Instructions: In this task, you're given a statement, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.
Input: Context: In 1977, Boyer's laboratory and collaborators Keiichi Itakura and Arthur Riggs at City of Hope National Medical Center described the first-ever synthesis and expression of a peptide-coding gene. Link Information: He obtained a PhD in Organic Chemistry at Tokyo Pharmaceutical College in 1970. Question: Which of Boyer's collaborators in 1977 completed their education first?
Output:
Answer: Arthur Riggs