In IFLA LRM's August 2017 edition, amended/corrected through December 2017, a manifestation (LRM-E4) groups carriers sharing content and physical-form characteristics under a production plan. An item (LRM-E5) is a particular object or group of objects carrying content. LRM-R4 connects a manifestation with the items that exemplify its characteristics.

A manifestation can be a singleton set, so multiple copies are not required. An item can comprise multiple objects, so it need not be one physical object. These distinctions extend beyond printed books, as illustrated by artwork, multi-disc, and ebook examples in this edition.

These claims are edition-specific; they establish neither latest-edition status nor a cataloguing-code prescription.

Source:

• IFLA Library Reference Model, August 2017, amended/corrected through December 2017; Table 4.2, LRM-E4 and LRM-E5; Table 4.7, LRM-R4