1. Beaujard F (1984) Culture in vitro des bruyeres et croissance rythmique chez L'Erica x darleyensis (Ericacees). Ph.D. Thesis, University of Angers, Angers, France.
2. Bressan PH, Kim YJ, Hyndman SE, Hasegawa PM & Bressan RA (1982) Factors affecting in vitro propagation of rose. J. Am. Soc. Hort. Sci. 107: 979?990.
3. Davidson CG (1986) Experimental taxonomy, propagation and models of inheritance for flower color and extra petals in Potentilla fruticosa L. Ph.D. Thesis, University of Manitoba, Winnipeg, Canada.
4. Innes RL, Remphrey WR & Lenz LM (1989) An analysis of the development of single and double flowers in Potentilla fruticosa. Can. J. Bot. 67: 1071?1079.
5. Juncker B & Favre JM (1989) Clonal effects in propagating oak trees via in vitro culture. Plant Cell Tiss. Org. Cult. 19: 267?276.