Betalains evolution

Stafford, H.A., Anthocyanins and betalains evolution of the mutually exclusive pathways. Plant ScL, 101, 91, 1994. 

Clement, J.S., Mabry, T.J., Wyler, H. and Dreiding, A.S. (1994) Chemical review and evolutionary significance of the betalains, in Caryophyllales, Evolution and Sys-tematics (eds H.-D. Behnke and T.J. Mabry). Springer-Verlag, Berlin Heidelberg, pp. 247-61. 

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