Which ABR Translates Type 7 to Type 5

In scenarios which there are more than one ABR connected to the NSSA area, only the ABR with the highest router-id may translate Type 7 LSA(s) to Type 5 LSA(s).

RFC 1587 - 3.4

http://gns3vault.com/OSPF/ospf-nssa-lsa-type-7-to-5-translator-election.html