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C. R. B. Baker, R. L. Blackman, M. F. Claridge, Studies on Haltica carduorum Guerin (Coleoptera: Chrysomelidae) an Alien Beetle Released in Britain as a Contribution to the Biological Control of Creeping Thistle, Cirsium arvense (L.) Scop., Journal of Applied Ecology, Vol. 9, No. 3 (Dec., 1972), pp. 819-830
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Baker et al. (1972) studied this question.
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