Robtex

Up: 63.99.28.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 63.99.29.0/25
Down right: 63.99.29.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
63.99.29.8	A	okcvpn.dvn.com
63.99.29.16	PTR	gw1-okc.dvn.com
63.99.29.16	A	ns7.dvn.com
63.99.29.18	A+PTR	gw3-okc.dvn.com
63.99.29.35	A+PTR	code.dvn.com
63.99.29.35	PTR	ochi.dvn.com
63.99.29.35	A+PTR	docs.dvn.com
63.99.29.40	A+PTR	gw7-okc.dvn.com
63.99.29.43	A+PTR	webmail.dvn.com
63.99.29.50	PTR	www.dvn.com
63.99.29.50	A	sip.dvn.com
63.99.29.50	A	xmpp.dvn.com
63.99.29.53	A+PTR	owa.ecm.dvn.com
63.99.29.53	PTR	lyncdiscover.dvn.com
63.99.29.53	PTR	odcedirweb.dvn.com
63.99.29.54	A+PTR	sip.dvn.com
63.99.29.54	A+PTR	xmpp.dvn.com
63.99.29.66	A+PTR	ftp.dvn.com
63.99.29.69	A+PTR	ns1.dvn.com
63.99.29.72	PTR	onecall.dvn.com
63.99.29.73	A+PTR	dskup.is.dvn.com
63.99.29.81	PTR	eftp.partners.dvn.com
63.99.29.92	A	omatest.dvn.com
63.99.29.95	PTR	mail21.dvn.com
63.99.29.95	A	wsmail.dvn.com
63.99.29.96	PTR	mail23.dvn.com
63.99.29.96	A	wsmail.dvn.com
63.99.29.118	A+PTR	onecall.dvn.com
63.99.29.135	PTR	ns8.dvn.com
63.99.29.135	A	wvsync.dvn.com
63.99.29.138	A	sunreports.dvn.com
63.99.29.149	A	jobs.dvn.com
63.99.29.149	A	devonicerink.com
63.99.29.149	A	devonadvocacynetwork.net
63.99.29.176	A	devonenergy.com
63.99.29.198	A	jointventures.dvn.com
63.99.29.200	A+PTR	ns5.dvn.com
63.99.29.235	A+PTR	ns2.dvn.com