¹ = The WHOIS protocol is US-ASCII only, as such only A-Z, a-z, 0-9 and a few other symbols are accepted. For instance if you need to write an umlaut you will need to use the 'ue' representation. Unrecognized characters are stripped from the query.
² = Don't forget to select the "SixXS" option when you are looking for a name in the SixXS database.
³ = When querying for a name, you will have to specify the registry to look at.
Using whois.sixxs.net as a whois server.
Querying for "2001:16d8:ff00:8000::/52".