Øllgaard, H.: Further new Taraxacum species (Asteraceae, Cichorieae) from northern Europe. — Willdenowia 36: 693–706. — ISSN 0511-9618; © 2006 BGBM Berlin-Dahlem. doi:10.3372/wi.36.36205 (available via http://dx.doi.org/)
Five new species of Taraxacum from northern Europe (T. freticola, T. leptoscelum, T. nigrescens, T. opertum, and T. palmgrenii) are validly named, described and discussed, and their known distribution is presented. All are members of T. sect. Ruderalia. For two species known by illegitimate names (later homonyms), new names are proposed: T. homoschistum, T. longiconicum.