(2019). 环 球．2019,no.13-16,20.
Chicago Style aipamena环 球．2019,no.13-16,20. 2019.
MLA aipamena环 球．2019,no.13-16,20. 2019.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.
APA aipamena
(2019). 环 球．2019,no.13-16,20.
Chicago Style aipamena环 球．2019,no.13-16,20. 2019.
MLA aipamena环 球．2019,no.13-16,20. 2019.