TY - JOUR A1 - Christensen, K. A1 - McGue, M. A1 - Yashin, A. A1 - Iachine, I. A1 - Holm, N.V. A1 - Vaupel, J.W. T1 - Genetic and environmental influences on functional abilities in Danish twins aged 75 years and older Y1 - 2000 JF - Journals of Gerontology: Series A - Biological Sciences and Medical Sciences VL - 55 IS - 8 SP - M446 EP - -M452 ER -