Robtex

Up: 189.51.192.0/19
Can't show all results, try to descend to a more specific CIDR
Down left: 189.51.208.0/21
Down right: 189.51.216.0/21
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
189.51.208.3	PTR	hosp.golnet.com.br
189.51.208.3	A	ns1.construirfacil.com.br
189.51.208.3	A	server.golnet.com.br
189.51.208.4	PTR	mail.golnet.com.br
189.51.221.236	PTR	srvproxy.edraaeronautica.com.br
189.51.221.236	A	edraescola.com.br
189.51.222.27	A+PTR	server.viviani.com.br
189.51.222.109	PTR	servidor03.nardiniceramica.com.br