Robtex

Up: 188.72.64.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 188.72.64.0/23
Down right: 188.72.66.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
188.72.64.1	PTR	asrv3.qwarta.ru
188.72.64.5	PTR	login.q0.ru
188.72.64.170	PTR	fiber.by.weserve.nl
188.72.65.5	PTR	pochta.q0.ru
188.72.65.13	PTR	asrv168.qwarta.ru
188.72.65.16	A	ns1.xeno.ru
188.72.65.52	PTR	fiber.by.weserve.nl
188.72.65.248	A	xn--80aaah3aaca2blwhqs3dt.xn--p1ai
188.72.65.248	A	xn--80aaaaaa6ca6bgfyeekiebd.xn--p1ai
188.72.65.248	A	xn--80aaad8aacaar1an0agdt2i.xn--p1ai
188.72.66.245	A	mail.beerzebulten.nl
188.72.67.1	A	ru.htmlns3.q0.ru
188.72.67.1	A	72.65.15.q0.ru
188.72.67.1	A	*.htmlasrv53.qwarta.ru