237.91.68.in-addr.arpa is a domain controlled by four nameservers. Two of them are on the same IP network. gwcf.net, swri.edu, cat2.com, swri.org, zzapp.org and at least 87 other hosts share nameservers with this domain. 91.68.in-addr.arpa is a domain controlled by three nameservers. Two of them are on the same IP network.