http://www.karadar.it/Dictionary/isaac.html Musica Classica Classical Music Dictionary article with brief life and facsimile of a Credo. http://www.hnh.com/composer/isaac.htm Short essay on his life and works. http://stevenestrella.com/composers/composerfiles/isaac1517.html Biographical data, recommended CDs, books and sheet music, bibliography, and links to biographical essays.