Strandberg Timo E, Pienimäki Tuula, Strandberg Arto Y, Salomaa Veikko V, Pitkälä Kaisu H, Tilvis Reijo S, Miettinen Tatu A
Institute of Health Sciences/Geriatrics, University of Oulu, Finland.
Arch Intern Med. 2011 May 23;171(10):941-3. doi: 10.1001/archinternmed.2011.183.