Robtex

Up: 91.237.64.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 91.237.64.0/25
Down right: 91.237.64.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
91.237.64.17	A+PTR	mx1.naftogaz.com
91.237.64.18	A+PTR	mx2.naftogaz.com
91.237.64.19	A+PTR	mail3.naftogaz.net
91.237.64.20	A+PTR	ugp.naftogaz.com
91.237.64.20	A	www.ukrtransgas.naftogaz.com
91.237.64.21	A+PTR	mail4.naftogaz.net
91.237.64.33	A+PTR	xn--80aair0ah1ap.xn--j1amh
91.237.64.33	PTR	www.naftogaz.com
91.237.64.33	A	teplo.info
91.237.64.34	PTR	www.mcboyarka.com
91.237.64.34	A	mcboyarka.com
91.237.64.36	A+PTR	at.naftogaz.com
91.237.64.36	A	monitor.naftogaz.com
91.237.64.46	A	da1.naftogaz.com
91.237.64.47	A	da2.naftogaz.com
91.237.64.133	A	mail.naftogaz.com