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

% [whois.apnic.net]
% Whois data copyright terms    http://www.apnic.net/db/dbcopyright.html

% Information related to 'MAINT-VN-HANOITELECOM'

mntner:         MAINT-VN-HANOITELECOM
descr:          Hanoi Telecom Corporation
descr:          No 2, Chua Boc Street, Dong Da District, Hanoi City
admin-c:        NHT6-AP
admin-c:        NBM1-AP
admin-c:        HTIN1-AP
tech-c:         TMH5-AP
tech-c:         HTIN2-AP
tech-c:         NXT9-AP
upd-to:         hm-changed@vnnic.net.vn
auth:           # Filtered
country:        VN
mnt-nfy:        hm-changed@vnnic.net.vn
referral-by:    APNIC-HM
mnt-by:         MAINT-VN-HANOITELECOM
remarks:        Maintainer for HANOITELECOM (VNNIC's member)
last-modified:  2013-05-31T04:07:55Z
source:         APNIC

person:         Hanoi Telecom IP Network Admin
nic-hdl:        HTIN1-AP
e-mail:         internet_admin@hanoitelecom.com
address:        Hanoi Telecom Corporation
address:        No 2, Chua Boc Street, Dong Da District, Hanoi City
phone:          +84-4-35735502
fax-no:         +84-4-35729834
country:        VN
mnt-by:         MAINT-VN-VNNIC
last-modified:  2013-05-31T03:42:02Z
source:         APNIC

person:         Hanoi Telecom IP Network Engineering
nic-hdl:        HTIN2-AP
e-mail:         internet_tech@hanoitelecom.com
address:        Hanoi Telecom Corporation
address:        No 2, Chua Boc Street, Dong Da District, Hanoi City
phone:          +84-4-35735502
fax-no:         +84-4-35729834
country:        VN
mnt-by:         MAINT-VN-VNNIC
last-modified:  2013-05-31T03:42:02Z
source:         APNIC

person:         Nguyen Binh Minh
nic-hdl:        NBM1-AP
e-mail:         minh.n@hanoitelecom.com
address:        Hanoi Telecom Corporation
address:        No 2, Chua Boc Street, Dong Da District, Hanoi City
phone:          +84-4-35729833
fax-no:         +84-4-35729834
country:        VN
mnt-by:         MAINT-VN-VNNIC
last-modified:  2013-05-31T03:42:02Z
source:         APNIC

person:         Nguyen Hong Thuy
address:        Hanoi Telecom Corporation
address:        No 2, Chua Boc Street, Dong Da District, Hanoi City
country:        VN
phone:          +84-4-5729833
fax-no:         +84-4-5729834
e-mail:         thuynh@pmu.hinet.net.vn
nic-hdl:        NHT6-AP
mnt-by:         MAINT-VN-HANOITELECOM
last-modified:  2008-09-04T07:31:38Z
source:         APNIC

person:         Nguyen Xuan Trung
nic-hdl:        NXT9-AP
e-mail:         trungnx@hanoitelecom.com
address:        Hanoi Telecom Corporation
address:        No 2, Chua Boc Street, Dong Da District, Hanoi City
phone:          +84-4-35735502
fax-no:         +84-4-35729834
country:        VN
mnt-by:         MAINT-VN-VNNIC
last-modified:  2013-05-31T03:42:03Z
source:         APNIC

person:         Tran Manh Hai
address:        Hanoi Telecom Corporation
address:        No 2, Chua Boc Street, Dong Da District, Hanoi City
country:        VN
phone:          +84-4-5729833
fax-no:         +84-4-5729834
e-mail:         haitm@hinet.net.vn
nic-hdl:        TMH5-AP
mnt-by:         MAINT-VN-HANOITELECOM
last-modified:  2008-09-04T07:31:38Z
source:         APNIC

% This query was served by the APNIC Whois Service version 1.88.25 (WHOIS-AU3)

Search for
IP address lookups			Miscellaneous queries
-l	1st level less specific		-i	Inverse attributes	None admin-c admin-c,tech-c,zone-c author cross-mnt cross-nfy local-as mbrs-by-ref member-of mnt-by mnt-lower mnt-nfy mnt-routes notify nserver origin person referral-by rev-srv sub-dom tech-c upd-to zone-c
-L	All less specific		-T	Object types	All as-block as-set aut-num domain filter-set inet-rtr inet6num inetnum irt key-cert mntner peering-set person role route route-set rtr-set
-m	1st level more specific
-M	All more specific		Query hints Include "AS" in front of an AS number. Example: AS4808 Include "-t" (template only) or "-v" (template and description) in front of an object name to view the template Example: -t inetnum
-x	Exact match only
-d	Associated reverse domain