5Whyte W H. The Social Life of Small Urban Spaces[M]. Project for Public Spaces Inc. 2001.
6Nilsson I , Lofgren B, Fisher A G , et al. Focus on Leisure Repertoire in the Oledst Old: The Umea 85+ Study[J]. Journal of,pplied Gerontology, 2006, 25(5): 391.
7Agahi N , Parker M G. Are today's older people more active than their predecessors? Participation in leisure-time activities in Sweden in 1992 and 2002[J]. Ageing and Society, 2002, 25(6): 925.