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LONG ANSWER: Generally speaking, a publisher's publisher’s statement about the edition is considered to be manifestation-level information. In Tracey's workshop example "Do androids dream of electric sheep?" as you can see on her cheat sheet released in Q-Tip #6, the edition statement "1st Ballantine Books trade pbk. ed." is assigned the entity level of Manifestation.
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Revision of: Roget, Peter Mark, 1779--1869. Thesaurus of English words and phrases.
While the publisher's statement "New edition" publisher’s statement “New edition” is at the manifestation level, "Revision of" is given as an example of "Derivative Expression Relationships" in RDA J.3.2:
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As Glen correctly pointed out in Tracey's presentation, however, it is possible to consider something like "Recreational problems in geometric dissections" as a new Work---if, after careful examination of the content, it is considered sufficiently different from the previously existing work. How to determine whether is it sufficiently different? RDA 6.27.1.5 gives this guidance:
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If one person, family, or corporate body is responsible for an adaptation or revision of a previously existing work that +substantially changes the nature and content of that work+ \ [metaserv:emphasis added\], and the adaptation or revision is presented as the work of that person, family, or body, construct the authorized access point representing the new work by combining (in this order):
a) the authorized access point representing the person, family, or body responsible for the adaptation or revision ... … and
b) the preferred title for the adaptation or revision
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