How does the wife of his noncontemporaneous brother [release her co-wives]? [There were] two brothers, one of whom died, and [then another] brother was born; subsequently, the second one performed yibum with his brother's widow and died —- the first is discharged as the wife of his noncontemporaneous brother, and the second as her co-wife. [If] he performed maamar with her and then died —- the second requires chalitzah but may not be taken in yibum.