found: Work cat.: Western waterhemlock, 1983:p. 2 of cover (Cicuta douglasii)
found: HortiPlex plant database, May 7, 2007(Cicuta douglasii; common name: western water hemlock)
found: ITIS * North America, May 7, 2007(Cicuta douglasii. Vernacular names: Douglas waterhemlock; Douglas' waterhemlock; water hemlock; western water hemlock)
found: GRIN taxonomy for plants, via WWW, May 7, 2007(Cicuta douglasii. Common name: western water-hemlock. Synonyms: Cicuta californica; Cicuta vagans; Sium douglasii)
found: WTU herbarium image collection, via WWW, May 7, 2007(Cicuta douglasii; western water-hemlock, Douglas' water-hemlock)
found: Plants database, via WWW, May 7, 2007(Cicuta douglasii, western water hemlock. Synonym: Cicuta maculata var. californica)
found: Burrows, G.E. Toxic plants of North America, 2000:p. 49 (Cicuta douglasii, Douglas water hemlock)
found: Wikipedia, July 24, 2007(Cicuta douglasii, Western water hemlock)