| Topic |
Reference |
| Mental Magic, Quadratic
Formula Inside Out |
Uncommon
Math Excursions |
| Four 9s Puzzle |
Howard Eves, "Hail
to thee, blithe spirit!", Fibonacci Quarterly, 19 (1981) 193-196. |
| Sum Formulas for Sine and
Cosine |
"Sum
Formulas for Sine and Cosine", Two-Year College Math Journal, 14
(1983) 55-56. |