title: Blue, green, and red upconversion emission from lanthanide-doped LuPO4 and YbPO4 nanocrystals in a transparent colloidal solution.
authors.affiliation: Department of Chemistry and Biochemistry, University of Bern, 3000 Bern 9, Switzerland.
authors.forename: Stephan
authors.initials: S
authors.lastname: Heer
authors.forename: Olaf
authors.initials: O
authors.lastname: Lehmann
authors.forename: Markus
authors.initials: M
authors.lastname: Haase
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Güdel