1. Cairns Th (ed): Modern Roses 10. American Rose Society, Shreveport (1993).
2. Kruessmann G.: The Complete Book of Roses. Timber Press, Portland (1981).
3. Short KC and Roberts AV: Rosa ssp. (Roses): In vitro culture, micropropagation, and the production of secondary products. In: Bajaj YPS (ed) Biotechnology in Agriculture and Forestry, vol. 15, pp. 376?397. Springer-Verlag, Heidelberg (1991).
4. Rohlf FJ/NTSYS-PC Numerical Taxonomy and multivariate Analysis System. Exeter Publishers, New York (1989).
5. Mitton JB: Molecular approaches to population biology. Annu Rev Ecol Syst 25: 45?69 (1994).