Trock & T.M.Barkley (Greenm.) 1998 - Trock DK, Barkley TM (1998) SEVEN NEW NOMENCLATURAL COMBINATIONS AND A NEW NAME IN PACKERA (ASTERACEAE: SENECIONEAE). Sida, Contributions To Botany 18(2): 385-387. Retrieved from http://www.jstor.org/stable/41967622