Baker Book House · RPM Auto Books
| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Porsche 356 Performance Guide | 978-0-9631726-4-8 (0-9631726-4-6) | 2009 |
| The Complete Porsche 912 Guide | 978-0-9631726-5-5 (0-9631726-5-4) | 2002 |
| Tulip: The Five Points of Calvinism in the Light of Scripture | 978-0-8010-6393-0 (0-8010-6393-0) | 2002 |
D S · D. Spencer · Duane E. Spencer · Duane Edward Spencer · Duane R. Spencer