International Symposium on Flower Bulbs Seattle, Wash, International Society for Horticultural Science. Section for Ornamental Plants, Chastagner, G. A., Doss, R. P., & Byther, R. S. (1990). Symposium on Flower Bulbs: Seattle, Washington, USA, 10-14 July 1989. International Society for Horticultural Science.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)International Symposium on Flower Bulbs Seattle, Wash, International Society for Horticultural Science. Section for Ornamental Plants, Gary A. Chastagner, Robert P. Doss, و Ralph S. Byther. Symposium on Flower Bulbs: Seattle, Washington, USA, 10-14 July 1989. Wageningen, Netherlands: International Society for Horticultural Science, 1990.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)International Symposium on Flower Bulbs Seattle, Wash, et al. Symposium on Flower Bulbs: Seattle, Washington, USA, 10-14 July 1989. International Society for Horticultural Science, 1990.