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

% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See https://docs.db.ripe.net/terms-conditions.html

% Note: this output has been filtered.
%       To receive output for a database update, use the "-B" flag.

% Information related to '83.231.136.0 - 83.231.136.127'

% Abuse contact for '83.231.136.0 - 83.231.136.127' is 'abuse@ntt.net'

inetnum:        83.231.136.0 - 83.231.136.127
netname:        VERIO-UK-INFRA
descr:          Verio UK london facility
country:        GB
admin-c:        NERA4-RIPE
tech-c:         NAIA1-RIPE
status:         ASSIGNED PA
remarks:        INFRA-AW
remarks:        Abuse/UCE: abuse@us.ntt.net
remarks:        Network: noc@us.ntt.net
remarks:        Security issues: security@us.ntt.net
mnt-by:         MAINT-VIPAR
created:        2005-11-14T19:46:45Z
last-modified:  2009-12-08T00:22:50Z
source:         RIPE # Filtered

role:           NTT IP Addressing
address:        5680 Greenwood Plaza Blvd.
address:        Greenwood Village, CO 80111
address:        United States
phone:          +1 (720) 475-4000
remarks:        Abuse/UCE: abuse@ntt.net
remarks:        Network: noc@ntt.net
remarks:        Security issues: security@ntt.net
admin-c:        NIR14-RIPE
tech-c:         NIR14-RIPE
nic-hdl:        NAIA1-RIPE
mnt-by:         MAINT-VIPAR
created:        2009-12-03T19:15:21Z
last-modified:  2023-02-07T18:56:12Z
source:         RIPE # Filtered
abuse-mailbox:  abuse@ntt.net

role:           NTT Europe Role Account
address:        NTT Europe, Ltd.
address:        Devon House
address:        58 - 60 St. Katharine's Way, 1st Floor
address:        London E1W 1LB
address:        United Kingdom
phone:          +44 20 7767 3700
fax-no:         +44 20 7767 3701
remarks:        Network: noc@us.ntt.net
remarks:        Abuse/UCE: abuse@us.ntt.net
remarks:        Security issues: security@us.ntt.net
admin-c:        NAIA1-RIPE
tech-c:         NAIA1-RIPE
nic-hdl:        NERA4-RIPE
mnt-by:         MAINT-VIPAR
created:        2009-12-03T19:18:33Z
last-modified:  2015-08-18T00:23:37Z
source:         RIPE # Filtered
abuse-mailbox:  abuse@ntt.net

% This query was served by the RIPE Database Query Service version 1.120 (ABERDEEN)