% 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://apps.db.ripe.net/docs/HTML-Terms-And-Conditions

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

% Information related to '91.233.56.0 - 91.233.59.255'

% Abuse contact for '91.233.56.0 - 91.233.59.255' is 'mohammadali@tavanir.org.ir'

inetnum:        91.233.56.0 - 91.233.59.255
netname:        Tavanir
country:        IR
org:            ORG-IPGt2-RIPE
admin-c:        RM12319-RIPE
tech-c:         RM12319-RIPE
status:         ASSIGNED PI
mnt-by:         RIPE-NCC-END-MNT
mnt-by:         AZMA-MNT
mnt-routes:     TAVANIR-MNT
mnt-domains:    AZMA-MNT
created:        2011-12-05T13:26:05Z
last-modified:  2023-11-02T09:20:50Z
source:         RIPE # Filtered
sponsoring-org: ORG-FACL1-RIPE

organisation:   ORG-IPGt2-RIPE
org-name:       Iran Power Generation transmission & Distribution Management Co.
country:        IR
org-type:       OTHER
address:        Shahid Abbaspour Ave., Vanak Sq., Tehran - IRAN
admin-c:        RM12319-RIPE
abuse-c:        AC30636-RIPE
phone:          +982127935346
fax-no:         +982188644990
mnt-ref:        AZMA-MNT
mnt-by:         AZMA-MNT
created:        2011-09-12T08:01:44Z
last-modified:  2022-12-01T16:31:25Z
source:         RIPE # Filtered

person:         Reza MohammadAli
address:        Shahid Abbaspour Ave., Vanak Sq., Tehran - IRAN
phone:          +982127935346
fax-no:         +982188644990
nic-hdl:        RM12319-RIPE
mnt-by:         AZMA-MNT
created:        2011-09-12T07:24:44Z
last-modified:  2011-09-12T07:24:44Z
source:         RIPE # Filtered

% Information related to '91.233.56.0/24as57577'

route:          91.233.56.0/24
descr:          First-b
origin:         as57577
mnt-by:         TAVANIR-MNT
created:        2011-12-18T09:17:01Z
last-modified:  2011-12-18T09:17:01Z
source:         RIPE

% This query was served by the RIPE Database Query Service version 1.111 (SHETLAND)

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