Robtex

Up: 138.99.0.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 138.99.4.0/23
Down right: 138.99.6.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
138.99.6.65	PTR	host65.138-99-6.telmex.net.ar
138.99.6.66	PTR	host66.138-99-6.telmex.net.ar
138.99.6.66	A	umatravel.com.ar
138.99.6.69	A	resistemas.com
138.99.6.77	PTR	host77.138-99-6.telmex.net.ar
138.99.6.77	A	booclass.com
138.99.6.82	PTR	mail.idr.org.ar
138.99.6.82	A	ecoatlas.org.ar
138.99.6.95	PTR	ackbar.infoar.net
138.99.6.95	A	discovertheandes.com.ar
138.99.6.95	A	www.clinicamira.com.ar
138.99.6.131	PTR	server18.puinsy.net
138.99.6.131	A	www.walibit.com.ar
138.99.6.131	A	puinsy.net
138.99.6.146	PTR	host146.138-99-6.telmex.net.ar
138.99.6.146	A	ns1.cristianliebana.com.ar
138.99.6.146	A	cloud2.cristianliebana.com.ar
138.99.6.147	PTR	host147.138-99-6.telmex.net.ar
138.99.6.161	A	ewavecifras.com
138.99.6.169	PTR	host169.138-99-6.telmex.net.ar
138.99.7.0	A+PTR	yoda.infoar.net
138.99.7.0	A	yancarelligomez.com.ar
138.99.7.0	A	lapayunia.com
138.99.7.17	PTR	host17.138-99-7.telmex.net.ar
138.99.7.27	A	www.aguasdeltucuman.com.ar
138.99.7.50	A	testinglm.com.ar
138.99.7.66	PTR	host66.138-99-7.telmex.net.ar
138.99.7.66	A	www.omargutierrez.com.ar
138.99.7.66	A	senku.com.ar
138.99.7.84	PTR	host84.138-99-7.telmex.net.ar
138.99.7.84	A	cloud.cristianliebana.com.ar
138.99.7.99	PTR	host99.138-99-7.telmex.net.ar
138.99.7.108	PTR	host108.138-99-7.telmex.net.ar
138.99.7.109	PTR	host109.138-99-7.telmex.net.ar
138.99.7.109	A	novitashealth.com
138.99.7.109	A	anitadedospuertos.com
138.99.7.111	PTR	host111.138-99-7.telmex.net.ar
138.99.7.111	A	gmclaro.com
138.99.7.116	A+PTR	watto.infoar.net
138.99.7.129	PTR	smtp.c-1.soslinux.com.ar
138.99.7.129	A	soslxzimc01.soslinux.com.ar
138.99.7.178	PTR	binario.com.ar