Robtex

Up: 212.252.40.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 212.252.40.0/23
Down right: 212.252.42.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
212.252.40.3	PTR	host-212-252-40-3.reverse.superonline.net
212.252.41.251	PTR	host-212-252-41-251.reverse.superonline.net
212.252.41.251	A	sip.tanap.com
212.252.41.253	A	av.tanap.com
212.252.41.254	PTR	host-212-252-41-254.reverse.superonline.net
212.252.42.3	PTR	asy3.as42.sol.superonline.com
212.252.42.3	A	mx.tahayapi.com
212.252.42.3	A	mail.tahagroup.net
212.252.42.5	PTR	host-212-252-42-5.reverse.superonline.net
212.252.42.5	A	mail.masg.com.tr
212.252.42.5	A	mail.zeytinstore.com
212.252.42.42	PTR	mail.itoplatformu.net
212.252.42.42	A	mail.cfyazilim.com
212.252.42.42	A	mail.texim.com.tr
212.252.42.142	PTR	mail.haldunboz.com
212.252.42.142	PTR	mail.interamila.com
212.252.42.142	PTR	mail.novafashiongroup.com
212.252.42.226	PTR	host-212-252-42-226.reverse.superonline.net
212.252.42.238	PTR	host-212-252-42-238.reverse.superonline.net
212.252.42.252	PTR	host-212-252-42-252.reverse.superonline.net
212.252.42.252	A	mail.elitkentvilla.com
212.252.42.252	A	mail.tahatransport.com
212.252.42.253	PTR	mail.globalveri.com
212.252.42.253	PTR	mail.pmgroup.tc
212.252.42.253	PTR	mail.iqgarden.com.tr
212.252.43.240	PTR	mail.codeconsultancy.com
212.252.43.240	A+PTR	mail.globaltmr.com
212.252.43.240	PTR	mail.novatrends.com
212.252.43.241	PTR	mail.codeconsultancy.com
212.252.43.241	PTR	mail.globaltmr.com
212.252.43.241	PTR	mail.golfdegolf.com