Williamson, E. M., By Okpako , D. T., & Evans , F. J. (1996). Pharmacological methods in phytotheropy: Research : selection, preparation and pharmacological evaluation of plant meterial. Wiley.
Čikaški stil citiranja (17. izdanje)Williamson, Elizabeth M., David T. By Okpako , i Fred J. Evans. Pharmacological Methods in Phytotheropy: Research : Selection, Preparation and Pharmacological Evaluation of Plant Meterial. New York: Wiley, 1996.
MLA način citiranja (9. izdanje)Williamson, Elizabeth M., et al. Pharmacological Methods in Phytotheropy: Research : Selection, Preparation and Pharmacological Evaluation of Plant Meterial. Wiley, 1996.
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