Norma
Opera by Vincenzo Bellini
Libretto by Felice Romani
A plot synopsis of Norma can be found at the site of the Metropolitan Opera.
Opera Pages johnrpierce.com
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Norma Libretto
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Norma in Full Score (paperback),
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Both of Maria Callas's studio recordings of Norma were conducted by Tullio Serafin.  The earlier of the two had Ebe Stignani as Adalgisa and Mario Filippeschi as Pollione; the latter had Christa Ludwig and Franco Corelli.  Over all, I prefer the later recording, but Callas's voice is fresher in the earlier.
Opera d'Oro has released, without a libretto, a recording of a "live" performance of Norma with Maria Callas, Ege Stignani, and Mario Del Monaco, conducted by Tullio Serafin.  Available from amazon.com.
Norma: in Full Score: (Sheet Music)
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Bellini - NORMA (MCD051306) with Joan Sutherland, Marilyn Horne,
Frano Tagliavini, Joseph Rouleau, From London, 1967, conducted by
Richard Bonynge.  Myto.

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Bellini - NORMA (Naxos 8110325-27) with Maria Callas, Mario Filippeschi, Ebe Stignani, Nicola Rossi-Lemeni, Chorus and Orchestra of Teatro alla Scala conducted by Tullio Serafin. This 1954 recording has been released in a new transfer made from the best portions of two 1950s-
era British LP pressings which provide the most open and un-gimicked sound of several editions previously available.

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Norma (G. Schirmer's Collection of Opera Librettos) (Paperback)
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