Video discussing my favorite operatic reference books
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Here is a list of my favorite
general purpose reference
books for opera

New Kobbé's Opera Book
Earl of Harewood and Anthony Peattie Editors
ISBN 978-0091814103
 
Great Operas Volumes I, II & III
By Ernest Newman

Wagner Operas (Also published as Wagner Nights)
By Ernest Newman
 
A Passion for Opera: Learning to Love It
By Peter Fox Smith
ISBN 978-1570762802
 
The Operagoers Guide:One Hundred Stories and Commentaries
By M. Owen Lee
ISBN 978-1574670653
 
Also mentioned in the video and recommended:
Stand Up Straight and Sing!
By Jessye Norman
Paperback ISBN 978-0544484054