Three items measure how strongly a person views an object or artefact as authenticating proof of a specific person's or event's existence — functioning as physical evidence of something real, rather than merely resembling it. Rooted in the indexical dimension of authenticity.
Grayson, K., & Martinec, R. (2004). Consumer perceptions of iconicity and indexicality and their influence on assessments of authentic market offerings. Journal of Consumer Research, 31(September), 296–312.
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