Flagstad apparently sang these on many recordings.  I happen to prefer the
piano accompanied version that Wagner wrote first and Flagstad has recorded
that w/ Bruno Walter (AS 422) and Gerald Moore (EMI 7 63030).

She's also recorded it w/ Oivin Fjeldstad conducting the Orchestra of the
Oslo Philharmonic society (Acanta 43 189).  Two other orchestral versions
that I have on CD are w/ Astrid Varnay and Leopold Ludwig conducting the
Bavarian Radio Symphony (DG 423 955) and Tiana Lemnitz w/ Robert Heger
conducting the Staatskapelle Berlin (Acanta 43 275).

There is also a performance by Eileen Farrell w/ Stokowski that I don't
think is available on CD but was available (along w/ much other music)
on a CD-ROM called "Wondrous Women" obtainable, at least at one time,
at a fantastical low price from the following Web Site

   http://mrichter.simplenet.com/

but which I could not locate when I accessed that site just now.

Walter Meyer