information Historical Whois of a NGTLD

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I'm researching the historical ownership of a NGTLD domain.

I've seen the history from multiple sources : Whoxy, Whoisfreaks etc.

But I can't get any info except the nameservers used. It says I need to use the registrar rdds service to get the details.

But registrar has only current Whois data. Any pointers on this ?