| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Spark | 978-1-61039-053-8 (1-61039-053-9) | 2011 |
| Spark: How Old-Fashioned Values Drive a Twenty-First-Century Corporation: Lessons from Lincoln Electric's Unique Guaranteed Employment Program | 978-1-58648-795-9 (1-58648-795-7) | 2010 |