V. G. Papatsiros, E. D. Tzika, P. D. Tassis, D. Kantas, L. C. Filippopoulos, and D. S. Papaioannou, “Greek experience of the use of phytogenic feed additives in organic pig farming”, African Journal of Pig Farming, vol. 7, no. 1, pp. 1–4, Jan. 2019.