ค้นหาชื่อบทความที่มีผู้เขียนคนแรกสังกัดสถาบันในประเทศ "ญี่ปุ่น" และมีนามสกุล "โอโฮริ"?
Find the titles of papers whose first author is affiliated with an institution in the country "Japan" and has last name "Ohori"?
authorship = pd.DataFrame(columns=['authid', 'paperid', 'instid', 'authorder']); authors = pd.DataFrame(columns=['authid', 'lname']); papers = pd.DataFrame(columns=['title', 'paperid']); inst = pd.DataFrame(columns=['instid', 'country'])
papers.loc[papers['paperid'].isin(authorship.loc[(authorship['authorder'] == 1) & (authors[authors['lname'] == 'Ohori']['authid']) & (inst[inst['country'] == 'Japan']['instid']), 'paperid']), 'title']