add Gallica's ebook links

[jum-s]

On a work page, there are already some links to eBooks from Gallica digital library, build from its Wikidata property: P4258.

The BNF documentation states that another Wikidata property is related to Gallica: the catalogue identifier P268, which seems to be much more in use on Wikidata (~4500 works) than P4258 (~100 works).

Note that both P4258 and P268 values are both ARK identifiers, but all manual attempts to access an eBook URL from P268 failed, including items with both P4258 and P268 values. ie. while expecting to open this Gallica ebook, the URL https://gallica.bnf.fr/ark:/12148/cb31293320w based on P268 value 31293320w, redirects to BNF catalogue... While basic search engine request does find the unique identifier in the book notice (prefix with cb: https://gallica.bnf.fr/services/engine/search/sru?operation=searchRetrieve&query=(gallica%20all%20%22cb31293320w%22)

Would it make sense to add a link to the entity search result page on Gallica ?