"Butterflies and plants: a study in coevolution" (1964) Evolution: 18 pp 586-608
Ehrlich, P.R. & Raven, P.H.
Reproduced by permission of The Society for the Study of Evolution.
The paper that, as much as any, stimulated modern research on coevolution. This paper was one of the first to examine the concept of community evolution and emphasise the reciprocal aspects of many types of interaction between organisms of different species.