Perez, D. (1999). Steel firm was bound to fail. Manila Bulletin.
Chicago Style aipamenaPerez, Delfin. "Steel Firm Was Bound to Fail." Manila Bulletin 1999.
MLA aipamenaPerez, Delfin. "Steel Firm Was Bound to Fail." Manila Bulletin, 1999.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.