Robtex

Up: 98.138.47.0/24
Can't show all results, try to descend to a more specific CIDR
Down left: 98.138.47.128/26
Down right: 98.138.47.192/26
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
98.138.47.128	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.129	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.130	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.131	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.132	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.134	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.135	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.136	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.137	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.141	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.142	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.144	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.146	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.147	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.149	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.151	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.156	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.160	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.162	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.163	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.164	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.166	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.168	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.170	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.171	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.176	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.177	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.178	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.179	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.180	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.181	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.182	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.184	PTR	gd.ads.vip.ne1.yahoo.com
98.138.47.184	A	pn1.adserver.a05.yahoodns.net
98.138.47.184	A	open.ad.yieldmanager.net
98.138.47.186	A+PTR	av-beap.adx.vip.ne1.yahoo.com
98.138.47.186	A	beapav.bc.gysm.yahoodns.net
98.138.47.190	PTR	smilenew.ysm.vip.ne1.yahoo.com
98.138.47.199	A+PTR	beap-csc.adx.vip.ne1.yahoo.com
98.138.47.199	A	csc.beap.ad.yieldmanager.net
98.138.47.199	A	any-beapcsc1.ysm.yahoodns.net
98.138.47.204	A+PTR	beap-yc.adx.vip.ne1.yahoo.com
98.138.47.204	A	ci.beap.ad.yieldmanager.net
98.138.47.204	A	beap.adx.yahoo.com
98.138.47.207	A	sastsummit.ysm.a04.yahoodns.net
98.138.47.211	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.212	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.214	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.216	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.219	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.225	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.226	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.227	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.229	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.230	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.231	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.233	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.234	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.236	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.240	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.241	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.242	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.243	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.245	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.247	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.250	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.251	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.252	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.254	PTR	unknown-98-138-47-x.yahoo.com
98.138.47.255	PTR	unknown-98-138-47-x.yahoo.com