@CONFERENCE\{IMM2006-04995, author = "B. B{\"{o}}dvarsson and M. M{\o}rkebjerg and L. Hansen and G. M. Knudsen and C. Svarer", title = "Extraction of time activity curves from positron emission tomography: {K-}means clustering or Non-negative matrix factorization", year = "2006", month = "jun", keywords = "{NMF,} {K-}means clustering, positron emission tomography", pages = "T185", booktitle = "NeuroReceptor Mapping 2006, Copenhagen, Denmark", volume = "31", series = "", editor = "NeuroImage", publisher = "", organization = "", address = "", url = "http://www.sciencedirect.com", isbn_issn = "1053-8119" }