title: Ultrasound-assisted extraction of alantolactone and isoalantolactone from Inula helenium roots.
authors.affiliation: Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
authors.forename: Antoaneta
authors.initials: A
authors.lastname: Trendafilova
authors.forename: Christo
authors.initials: C
authors.lastname: Chanev
authors.forename: Milka
authors.initials: M
authors.lastname: Todorova