| Nr. | Authors/Editors | Title | Year | Price in Dollars |
| 6. | Abramsky/ Gabbay/ Maibaum | Handbook of Logic in Computer Science Vol. 3 - Semantic Structures (antiquarian) | 1994 | ca. 150.00 |
| 7. | Wechler, Wolfgang | Universal Algebra for Computer Scientists (antiquarian) | 1992 | ca. 120.00 |
  Siden vedlikeholdes av Uwe Wolter |