Robtex

Up: 213.144.50.0/24
Can't show all results, try to descend to a more specific CIDR
Down left: 213.144.50.0/26
Down right: 213.144.50.64/26
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
213.144.50.64	A+PTR	mercancias.renfe.es
213.144.50.66	PTR	www.irionrenfe.com
213.144.50.66	PTR	pecovasarenfe.es
213.144.50.66	PTR	www.contrenrenfe.com
213.144.50.76	A+PTR	renfe.es
213.144.50.76	A+PTR	nube.renfe.com
213.144.50.77	A+PTR	utetilo.com
213.144.50.77	A+PTR	www.utetilo.com