Allen, E. B., McDonald, C., Hilbig, B. E., (2019). General Technical Report - Pacific Southwest Research Station, USDA Forest Service(No.GTR-PSW-265), 1-18. Pacific Southwest Research Station, USDA Forest Service, Berkeley, USA. English language
Hilbig, B. E., Allen, E. B., (2019). Invasive Plant Science and Management 12(3), 186-193. Weed Science Society of America, Lawrence, USA. English language
Horváth, J., (1991). Acta Phytopathologica et Entomologica Hungarica 26(3-4), 347-351. English language
USA, University of Illinois (1987) External factsheets, University of Illinois, 8 pp., English language