Optionally, the relationship of an observation to its image and image coordinates can be encoded with by-reference Content Items as Figure I.5-1 shows. For conciseness, the by-reference relationship points to the Content Item in the Image Library, rather than directly to the image.

R-INFERRED FROM relationships to IMAGE Content Items specify that the image supports the observation. A purpose of reference in an SCOORD Content Item may specify an analytic operation (performed on that image) that supports or produces the observation.