| No. | Title | Jounal or Publisher | Year | etc |
|---|---|---|---|---|
| 1 | The Diffusion of Counting Practices by A. Seidenberg | University of California Publications in Mathematics, Vol. 3, No. 4, pp. 215-300, plate 1, 8 figures in text, 2 maps | 1960 | Map 1. The pure 2- and neo-2-systems |
| 2 | The Diffusion of Counting Practices by A. Seidenberg | University of California Publications in Mathematics, Vol. 3, No. 4, pp. 215-300, plate 1, 8 figures in text, 2 maps | 1960 | Map 2. Finger counting |
| 3 | Theatrum Arithmetico-Geometricum by Jacob Leupold | 1727 | ||
| 4 | Africa Counts: Number and Pattern in African Culture by Claudia Zaslavsky | Lawrence Hill Books | 1999 | |
