n.d. · N Douglas · Nigel B Douglas · Nigel G. Douglas
| title | media type | ISBN-13 | year of publication |
|---|---|---|---|
| Legendary Voices | Paperback | 978-0-87910-187-9 | 1995 |
| Legendary Voices | " | 978-0-233-98847-4 | 1993 |
| Legendary Voices | Hardcover | 978-0-233-98790-3 | 1992 |
| More Legendary Voices | " | 978-0-87910-193-0 | 2004 |
| More Legendary Voices | " | 978-0-233-98889-4 | 1994 |
| The Joy of Opera | Paperback | 978-0-233-00005-3 | 2004 |