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||Rondes et enfantines
This seems to have been given Op.34 at a later date, according to Worldcat.
Grammatically the title should be Rondes enfantines (childrens' dances) and so it is starting with the 2nd set, 15 Nouvelles rondes enfantines, Op.37 published the same year (there are also later sets including some published in 1918). Since this is the only set with the title "Rondes et enfantines", this is not "Book No.1" but just the whole thing.