26.51.193.in-addr.arpa is delegated to four nameservers, however two delegated nameservers are missing in the zone. Two of them are on the same IP network. cru.fr, ecp.fr, fdn.fr, uhb.fr, urec.fr and at least 64 other hosts share nameservers with this domain. 51.193.in-addr.arpa is a domain controlled by three nameservers. All of them are on different IP networks.