1. Effect of pH and concentration of the anthocyanin-flavonol co-pigment complex on the colour of ‘Better Times’ roses;Asen;J. Am. Soc. Hortic. Sci.,1971
2. Effect of pH, anthocyanin and flavonoid co-pigments on the color of statice flowers;Asen;J. Am. Soc. Hortic. Sci.,1973
3. Flower pigment composition of natural bud-variants among hybrid Chinese Azaleas, Rhododendron simsii (Planch.);De Loose;J. Hortic. Sci.,1970
4. A hypothesis on the inheritance of flower colours and flavonoids in Rhododendron simsii Planch;Heursel;Z. Pflanzenzücht.,1977
5. Royal Horticultural Society Colour Chart;Royal Horticultural Society,1966