question: Which papers' first author is affiliated with an institution in the country "Japan" and has last name "Ohori"? Give me the titles of the papers.
#1 return papers 
#2 return first authors of #1 
#3 return last names of #2 
#4 return #1 where #3 is  Ohori 
#5 return institutions that  #2 are affiliated with  
#6 return countries of #5 
#7 return #1 where #6 is  Japan 
#8 return #1 in both #4 and #7 
#9 return the   titles of #8