Robtex

Up: 145.216.0.0/15
Can't show all results, try to descend to a more specific CIDR
Down left: 145.217.0.0/17
Down right: 145.217.128.0/17

IP	Type	Hostname
145.217.0.75	PTR	145.217.early-registration.of.surfnet.invalid
145.217.1.2	PTR	145.217.early-registration.of.surfnet.invalid
145.217.5.2	PTR	145.217.early-registration.of.surfnet.invalid
145.217.14.2	PTR	145.217.early-registration.of.surfnet.invalid
145.217.151.213	PTR	145.217.early-registration.of.surfnet.invalid