>

Mandatory elements

A manifestation element is either mandatory or optional. A cataloguing agency must record at least one occurrence of a mandatory element. A cataloguing agency may choose not to record any occurrence for an optional element.

The mandatory requirement of an element is satisfied if a cataloguing agency records an occurrence of one of its element sub-types. This is a consequence of the semantic hierarchy of elements.

A mandatory element is indicated in ISBDM by the symbol before the reference information for the element.

An element may be mandatory if a condition is satisified; for example that there is a value that is applicable and available. A conditional mandatory stipulation is indicated in ISBDM by the symbol before the condition.

Record an element that is applicable and available at the finest level of granularity in a semantic hierarchy, including a sub-type of an element that is marked as mandatory.

All other elements are optional.