% 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 '213.226.53.0 - 213.226.53.255'

% Abuse contact for '213.226.53.0 - 213.226.53.255' is 'RIPE.Abuse@a1.bg'

inetnum:        213.226.53.0 - 213.226.53.255
netname:        MTELNET
descr:          Internet NAT Pool for GPRS Users
remarks:        INFRA-AW
descr:          INFRA-AW for Project "GRPS"
descr:          Responsible Devision for Project: ITS
country:        BG
admin-c:        MTC41-RIPE
tech-c:         MTC41-RIPE
status:         ASSIGNED PA
mnt-by:         ROUTE-12716-MNT
created:        2007-10-24T14:12:27Z
last-modified:  2007-10-24T14:12:27Z
source:         RIPE

% Information related to '213.226.0.0/18AS8717'

route:          213.226.0.0/18
descr:          A1 Bulgaria EAD.
origin:         AS8717
mnt-by:         AS12716-MNT
mnt-by:         SPNET-MNT
created:        2020-02-19T06:52:11Z
last-modified:  2020-02-19T06:52:11Z
source:         RIPE

% This query was served by the RIPE Database Query Service version 1.124.1 (BUSA)