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J.  Agren and Schemske, D. W., ?The cost of defense against herbivores: an experimental study of trichome production in Brassica rapa?, American Naturalist, vol. 41, pp. 338 - 350, 1993.

S. T.  Behmer and Joern, A., ?Diet choice by grass-feeding grasshopper based on the need for a limiting nutrient?, Functional Ecology, vol. 7, pp. 522 - 527, 1993.

P.  Abrams and Matsuda, H., ?Effects of adaptive predatory and anti-predator behaviour in a two-prey-one-predator system?, Evolutionary Ecology, vol. 7, pp. 312 - 326, 1993.

M. R.  Berenbaum and Zangerl, A. R., ?Furanocoumarin metabolism in Papilio polyxenes - Biochemistry, genetic variability, and ecological significance.?, Oecologia, vol. 95, pp. 370 - 375, 1993.

P. A.  Abrams, ?Optimal traits when there are several costs: the interaction of mortality and energy costs in determining foraging behavior?, Behavioral Ecology, vol. 4, pp. 246 - 253, 1993.

R. S.  Anderson, ?Weevils and plants - phylogenetic versus ecological mediation of evolution of host plant associations in Curculioninae (Coleoptera, Curculionidae).?, Memoirs of the Entomological Society of Canada, vol. 165, pp. 197 - 232, 1993.