"P81 ongoing throughout"@en . "Scope note:\nThis property describes the minimum period of time covered by an E52 Time-Span.\n\nSince Time-Spans may not have precisely known temporal extents, the CRM supports statements about the minimum and maximum temporal extents of Time-Spans. This property allows a Time-Span\u2019s minimum temporal extent (i.e. its inner boundary) to be assigned an E61 Time Primitive value. Time Primitives are treated by the CRM as application or system specific date intervals, and are not further analysed.\n\nExamples:\n- the time-span of the development of the CIDOC CRM (E52) ongoing throughout 1996-2002 (E61)\n\nIn First Order Logic:\nP81 (x,y) \u2283 E52(x)\nP81 (x,y) \u2283 E61(y)"@en . . "P81"^^ . .