% APNIC found the following authoritative answer from: whois.apnic.net

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% Information related to '42.1.64.0 - 42.1.127.255'

% Abuse contact for '42.1.64.0 - 42.1.127.255' is 'hm-changed@vnnic.vn'

inetnum:        42.1.64.0 - 42.1.127.255
netname:        MOBIFONE-VN
descr:          Mobifone Corporation
descr:          01 Pham Van Bach, Cau Giay, Ha Noi
country:        VN
admin-c:        DDD5-AP
tech-c:         DQD3-AP
tech-c:         VDL1-AP
status:         ALLOCATED PORTABLE
mnt-by:         MAINT-VN-VNNIC
mnt-lower:      MAINT-VN-VNNIC
mnt-irt:        IRT-VNNIC-AP
abuse-c:        DQD3-AP
last-modified:  2023-03-27T03:33:48Z
source:         APNIC

irt:            IRT-VNNIC-AP
address:        Ha Noi, VietNam
phone:          +84-24-35564944
fax-no:         +84-24-37821462
e-mail:         hm-changed@vnnic.vn
abuse-mailbox:  hm-changed@vnnic.vn
admin-c:        NTTT1-AP
tech-c:         NTTT1-AP
auth:           # Filtered
mnt-by:         MAINT-VN-VNNIC
last-modified:  2025-11-17T23:08:34Z
source:         APNIC

person:         Doan Dinh Dan
address:        Mobifone Corporation
country:        VN
phone:          +84-24-37831770
e-mail:         dan.doan@mobifone.vn
nic-hdl:        DDD5-AP
mnt-by:         MAINT-VN-VNNIC
last-modified:  2017-11-19T02:44:57Z
source:         APNIC

person:         Do Quang Duong
address:        MOBIFONE-VN
country:        VN
phone:          +84-2437831769
e-mail:         duong.do@mobifone.vn
nic-hdl:        DQD3-AP
mnt-by:         MAINT-VN-VNNIC
last-modified:  2021-07-01T11:29:06Z
source:         APNIC

person:         Vu Dinh Long
address:        MOBIFONE-VN
country:        VN
phone:          +84-903488383
e-mail:         long.vudinh@mobifone.vn
nic-hdl:        VDL1-AP
mnt-by:         MAINT-VN-VNNIC
last-modified:  2023-03-27T03:32:11Z
source:         APNIC

% Information related to '42.1.70.0/24AS131429'

route:          42.1.70.0/24
origin:         AS131429
descr:          Vietnam Internet Network Information Center (VNNIC)
                18 Nguyen Du Str, Hai Ba Trung District, Hanoi City, Vietnam
                24th floor, VNTA Tower, Duong Dinh Nghe, Cau Giay, Hanoi
mnt-by:         MAINT-VN-VNNIC
last-modified:  2021-10-01T04:25:13Z
source:         APNIC

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