http://geo.web.ru/druza/index.html

http://geol.hit.bg/ Ianko Gerdjikov, Geology of Sakar Mnt.

http://earthandman.hit.bg/ National Museum "Earth and man" - Sofia, Bulgaria

http://www.msgpa.edu.ru Moscow State Geological Prospecting Academy

http://www.minerant.org/ Mineral Collectors Page

http://www.sarfotostock.com/bosnianminerals/ Minerals from Bosnia and Herzegovina

http://www.catalogmineralov.ru/ Catalogue mineral

Agates from Sudetes - Poland and Czech

Anton Ivanov -

HIGH QUALITY MINERALS FROM BULGARIA, RUSSIA, KAZAKHSTAN, ETC.