"mixed league" is a phrase which has a couple of different meanings, depending on the point of reference.
In ABC (should I be using USBC now?) terms, a mixed league is one in which members sanction in both ABC and WIBC. Simply having a female bowl in a league does not make it a mixed league in ABC's eyes.
Leagues can have different definitios of "mixed", depending on team composition, distribution, etc. Most common people consider it a mixed league if there is any combination of the sexes.
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