% 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 '203.151.120.0 - 203.151.121.255'

% Abuse contact for '203.151.120.0 - 203.151.121.255' is 'op-network@inet.co.th'

inetnum:        203.151.120.0 - 203.151.121.255
netname:        PCD-TH
descr:          Pollution Control Department
descr:          404 Pahonyothin, Center Bldg, Payathai, Bangkok
country:        TH
admin-c:        INR1-AP
tech-c:         INR1-AP
mnt-by:         MAINT-TH-INET
status:         ASSIGNED NON-PORTABLE
last-modified:  2008-09-04T07:27:25Z
source:         APNIC

role:           INET NOC ROLE
address:        1768 Thai Summit Tower, New Petchburi Road
address:        Khet Huay Khwang, Bangkok
address:        Thailand 10310
country:        TH
phone:          +662 02 2577000
fax-no:         +662 02 2577275
e-mail:         noc@inet.co.th
remarks:        send spam and abuse reports to noc@inet.co.th
admin-c:        CN7-AP
tech-c:         AP224-AP
tech-c:         HN192-AP
tech-c:         NL276-AP
nic-hdl:        INR1-AP
remarks:        http://www.inet.co.th
notify:         noc@inet.co.th
mnt-by:         MAINT-TH-INET
last-modified:  2015-12-15T04:15:05Z
source:         APNIC

% Information related to '203.151.112.0/20AS4618'

route:          203.151.112.0/20
origin:         AS4618
descr:          Internet Thailand Company Ltd.
                1768 IFCT Tower, 10th-12th FL
                IT Floor New Petchburi Road
                Khwaeng Bang Kapi
                Khet Huay Khwang
mnt-by:         MAINT-TH-INET
last-modified:  2020-11-19T08:24:26Z
source:         APNIC

% This query was served by the APNIC Whois Service version 1.88.25 (WHOIS-AU2)

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