I want to use SLANT for a non profit charity website but there are no details about the author and no copyright info...can anyone advise?

See this thread about Zelek.

Created 20 years ago, by a creator that don't include his name (or alias, or other identification) in the parameters and don't add a file with his contact informations.
I think it'll be difficult to find him to ask a use permission...

Thanks.