International Symposium on the Flora of Ethiopia and Eritrea Carlsberg Academy, Friis, I., & Ryding, O. (2001). Biodiversity research in the Horn of Africa region: Proceedings of the Third International Symposium on the Flora of Ethiopia and Eritrea at the Carlsberg Academy, Copenhagen, August 25-27, 1999. Royal Danish Academy of Sciences and Letters.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रInternational Symposium on the Flora of Ethiopia and Eritrea Carlsberg Academy, Ib Friis, और Olof Ryding. Biodiversity Research in the Horn of Africa Region: Proceedings of the Third International Symposium on the Flora of Ethiopia and Eritrea at the Carlsberg Academy, Copenhagen, August 25-27, 1999. Copenhagen: Royal Danish Academy of Sciences and Letters, 2001.
एमएलए (9वां संस्करण) प्रशस्ति पत्रInternational Symposium on the Flora of Ethiopia and Eritrea Carlsberg Academy, et al. Biodiversity Research in the Horn of Africa Region: Proceedings of the Third International Symposium on the Flora of Ethiopia and Eritrea at the Carlsberg Academy, Copenhagen, August 25-27, 1999. Royal Danish Academy of Sciences and Letters, 2001.