1. Anthocyanins, flavones, xanthones;Blank,1958
2. Flavonoids: distribution and contribution to plant colour;Harborne,1965
3. The effect of temperature and light on colour of Rosa flowers;Shisa;Jap. Soc. hort. Sci.,1964
4. Petal blackening in ‘Baccara’ roses;Zieslin;J. Amer. Soc. hort. Sci.,1969