B0048. (Leonard Warren) Mary Jane Phillips-Matz. Leonard Warren, American Baritone. Portland, OR, Amadeus, 2000. 471pp. Index; Bibliography; Exhaustive Crawford Discography; Exhaustive Chronology; Photos; DJ. - 9781574670530
"[Warren's] remarkable voice had a dramatic intensity which did not come naturally to him. As with everything else in his life, he worked at that until he got it right. Fortunately, his incomparable voice and dramatic power are still available to us on recordings of some of his most famous roles....[He] became one of the most famous and beloved operatic baritones in the world....Warren's flawless technique, seamless flow of sound, and brilliant top voice were his vocal trademarks and these qualities became the standard by which others would be measured, including me."
- Sherrill Milnes, AMERICAN ARIA, pp.76-77