International Protea Research Symposium San Diego, Calif, International Society for Horticultural Science. Protea Working Group, International Society for Horticultural Science. Section for Ornamental Plants, Criley, R. A., & Parvin, P. E. (1990). Second International Protea Research Symposium: San Diego, California, U.S.A., March 7-8, 1989. International Society for Horticultural Science.
Chicago-viite (17. p.)International Protea Research Symposium San Diego, Calif, International Society for Horticultural Science. Protea Working Group, International Society for Horticultural Science. Section for Ornamental Plants, Richard A. Criley, ja Philip Eugene Parvin. Second International Protea Research Symposium: San Diego, California, U.S.A., March 7-8, 1989. Wageningen, Netherlands: International Society for Horticultural Science, 1990.
MLA-viite (8. p.)International Protea Research Symposium San Diego, Calif, et al. Second International Protea Research Symposium: San Diego, California, U.S.A., March 7-8, 1989. International Society for Horticultural Science, 1990.