[If] four brothers were married to four women and [then] died, if the eldest of them wished to perform yibum with all of them, he may do so.  [If] someone was married to two women and [then] died, conjugal relations or chalitzah with one of them releases her co-wife. [If] one was qualified and one was disqualified, if he is [going] to perform chalitzah, he should do so with the disqualified one; but if he is [going] to perform yibum, he may do so with the qualified one.