What style will you use and how do you plan to identify which volume you are referring to when you cite it, if not in the Bibliography? Will it be a footnote? If so just add the additional text of volume (and page nos.). If a Author, YEAR citation, if consistent with the style of the publisher, you might consider using the right click, edit citation route, each time citing the whole book and using the suffix field to indicate which volume and page if appropriate.
The style I want to use is not a the Endnote libray, but it’s similar to Eighteenth-Century Studies. All the references will be in footnotes, and there will be a bibliography too.
In such a style, the field Suffix doesn’t work.
And I would like not to enter the n° of volume in the “Pages” field. Indeed, if I do so, the “Ibid” function in multiple citations is disharmonious. I would obtain:
Then it sounds to me like you will have to add each volume and at the end of the day, before submitting, on a copy unlink the bibliography and delete all but one of the references to the book, and modify it accordingly. There would be know other way I can think of to trick endnote into only listing it once and to still maintain the correct footnoting.