LAC practice: Do not use field 775 to link different expressions of monographs (earlier editions, reprints, etc.). For government monograph documents published separately in English and French simultaneously, continue to use a 500 note "Issued also in French under title:     ." instead of 130 $l or 775. 

LAC practice: Related expression is also a core element for most serial relationships, such as "Continuation of," "Continued by", etc.  Prefer using MARC 7XX subfield $i or specifically-defined MARC tags (e.g., MARC field 785 for "Continued by") rather than MARC 5XX fields for recording relationships to related expressions.  Give reciprocal relationships when appropriate. Use field 775 to link different editions of the same serial.

LAC practice: Do not link different expressions: for instance, re-releases, or albums published under different formats, e.g. compact disc and vinyl.  According to 27.1, this appears to be a core element only for reproductions, and only if the content is identical. As soon as the content is revised (additional track or missing track, re-mix, etc.), do not link, even for reproductions.

LAC practice: Related expression is a core element for LAC for compilations: give a MARC 505 contents note unless the contents are indicated in another part of the description (e.g., in MARC 245 $a because no collective title is present). There is no limit on the number of expressions in the contents note unless burdensome.

When the original expression and one translation are in a compilation, give an analytical authorized access point for each expression. If the compilation contains the original expression and more than one translation, give analytical authorized access points for the original expression and at least one translation.

For other compilations of expressions, give an analytical authorized access point for the predominant or first expression in the compilation when it represents a substantial part of the resource. Disregard contributions such as a preface or introductory chapter. Generally, do not apply this core element to anthologies of poetry, hymnals, conference proceedings, journals, collections of interviews or letters, and similar resources.