21. | | Autor: Frangialli, Francesco | |
22. | | Autor: Sahulata, Max J. | |
23. | | Autor: Valene, L. Smith | |
24. | | Autor: Hall, Michael C. | |
25. | | Autor: Goût, Jacques | |
26. | | Autor: Ahmed, Zafar U. Coautor: ; Heller, Victor L. Hughes, Kevin A. | |
27. | | Autor: Aidi, Osmane | |
28. | | Autor: Behringer, Zsuzsanna | |
29. | | Autor: Kraft, Péter | |
30. | | Autor: Williams, Allan M. Coautor: ; Baláz, Vladimír | |