This question came up the other day during a conversation with my colleagues:
In the US, multipart monographs are described comprehensively or analytically, while the hierarchical description is rarely used. (see LC-PCC PS to RDA 1.5.4: „LC practice for general cataloging/PCC practice: Do not create hierarchical descriptions.“).
In contrast to the Anglo-American region, multipart resources are described hierarchically and comprehensively in Germany. The comprehensive description as part of a hierarchical description is referred to as parent record, while the analytical description as part of a hierarchical description is referred to as subordinate record. Subordinate records are differentiated into records for parts with independent titles and records for parts with dependent titles.
Example for a part with an independent title:
100 1 $aTolkien, John Ronald Reuel
245 14$aThe fellowship of the Ring
490 0 $aThe Lord of the Rings$v / John Ronald Reuel Tolkien ; Part 1
800 $aTolkien, John Ronald Reuel$tThe Lord of the Rings$b / John Ronald Reuel Tolkien$vPart 1$91.1979$w(DE-601)331832429
245 14$aThe Lord of the Rings$cJohn R. R. Tolkien
Example for a part with a dependent title:
245 00$aEncyclopedia of physics$nVol. 2$p[M - Z]$ced. by Rita G. Lerner and George L. Trigg
245 00$aEncyclopedia of physics$ced. by Rita G. Lerner and George L. Trigg
Standing orders are usually linked to the parent descriptions. When a new volume is received, it is inventoried at the parent record. This is why the Codex should support links between the hierarchy levels. I am not quite sure whether the element “series” alone is sufficient for this.