f:Extension extension with URL = 'code': maximum cardinality of 'extension' is 1 extension with URL = 'period': maximum cardinality of 'extension' is 1 value[x]: maximum cardinality of 'value[x]' is 0 f:Extension/f:extension id: maximum cardinality of 'id' is 1 url: minimum cardinality of 'url' is 1 url: maximum cardinality of 'url' is 1 value[x]: maximum cardinality of 'value[x]' is 1 id: maximum cardinality of 'id' is 1 url: minimum cardinality of 'url' is 1 url: maximum cardinality of 'url' is 1 value[x]: minimum cardinality of 'value[x]' is 1 value[x]: maximum cardinality of 'value[x]' is 1 f:Extension/f:extension/f:value[x] 1 id: maximum cardinality of 'id' is 1 text: maximum cardinality of 'text' is 1 f:Extension/f:extension/f:value[x]/f:coding 1 id: maximum cardinality of 'id' is 1 system: maximum cardinality of 'system' is 1 version: maximum cardinality of 'version' is 1 code: maximum cardinality of 'code' is 1 display: maximum cardinality of 'display' is 1 userSelected: maximum cardinality of 'userSelected' is 1