Kalantzi, O.I., Alcock, R.E., Johnston, P.A., Santillo, D., Stringer, R.L., Thomas, G.O. and Jones, K.C. (2001). The Global Distribution of PCBs and Organochlorine Pesticides in Butter. Environ. Sci. Technol. 35(6): 1013-1018.
Kalantzi, O.I., Alcock, R.E., Johnston, P.A., Santillo, D., Stringer, R.L., Thomas, G.O. and Jones, K.C. (2001). The Global Distribution of PCBs and Organochlorine Pesticides in Butter. Environ. Sci. Technol. 35(6): 1013-1018.