Preel, M. Plastic, chemical pollution beyond planet's safe limit - study. Manila Bulletin.
芝加哥风格引文Preel, Marc. "Plastic, Chemical Pollution Beyond Planet's Safe Limit - Study." Manila Bulletin .
MLA引文Preel, Marc. "Plastic, Chemical Pollution Beyond Planet's Safe Limit - Study." Manila Bulletin, .
警告：这些引文格式不一定是100％准确.