National Council for Voluntary Organisations (Great Britain). (1999). The Voluntary agencies directory, 1999 (18th ed.). NCVO Publications.
芝加哥风格引文National Council for Voluntary Organisations (Great Britain). The Voluntary Agencies Directory, 1999. 18th ed. London: NCVO Publications, 1999.
MLA引文National Council for Voluntary Organisations (Great Britain). The Voluntary Agencies Directory, 1999. 18th ed. NCVO Publications, 1999.
警告：这些引文格式不一定是100％准确.