used as reference constraint (Q21528959)
type of constraint for Wikidata properties: used to specify that a property must only be used in references or instances of citation
Language:
(P279) (Q21502402)
(P1366) (Q53869507)
(P1535) (Q54826158)
(Q54812269)
(P1813) "Source" (language: en)
"forrás" (language: hu)
"来源" (language: zh-hans)
"Παραπομπή" (language: el)
"vir" (language: sl)
(P1889) (Q21528958)
(Q21510863)
(P2559) "用作P2302(属性约束)的值" (language: zh-hans)
"use as value for P2302 (property constraint)" (language: en)
other details
aliases source-only constraint
reference-only constraint
description type of constraint for Wikidata properties: used to specify that a property must only be used in references or instances of citation

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