Orig, T. S. (2001). Wind-electric water pumping is good for Visayas, says firm. Manila Bulletin.
Chicago-viite (17. p.)Orig, Thor S. "Wind-electric Water Pumping Is Good for Visayas, Says Firm." Manila Bulletin 2001.
MLA-viite (9. p.)Orig, Thor S. "Wind-electric Water Pumping Is Good for Visayas, Says Firm." Manila Bulletin, 2001.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.