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4. Baker, H.G. (1975) Sporophyte-gametophyte interactions in Linum and other genera with heteromorphic incompatibility. In: D.L. Mulcahy (ed.), Gamete Competition in Plants and Animals, pp. 191–200. North-Holland Publ., Amsterdam.
5. Barrett, S.C.H. (1988a) The evolution, maintenance, and loss of self-incompatibility systems. In: J. Lovett Doust and L. Lovett Doust (eds.), Plant Reproductive Ecology. Patterns and Strategies, pp. 98–124. Oxford University Press, New York.