Robtex

Up: 200.47.28.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 200.47.29.0/25
Down right: 200.47.29.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
200.47.29.17	A+PTR	mail2.grupocapsa.com.ar
200.47.29.20	A+PTR	mail6.grupocapsa.com.ar
200.47.29.20	A	mail6.capex.com.ar
200.47.29.106	PTR	bt1.cgc.com.ar
200.47.29.138	A+PTR	mail.dmetrop.com.ar
200.47.29.138	A	mx.dmetrop.com.ar
200.47.29.138	A	mx.cruzdelvalle.com
200.47.29.141	A	pop3.dmetrop.com.ar
200.47.29.141	A	smtp.dmetrop.com.ar
200.47.29.142	PTR	adsl-com-2-142.smandes.com.ar
200.47.29.142	A	mx1.cruzdelvalle.com
200.47.29.142	A	mx1.dmetrop.com.ar