Żaba, J., & Gaidzik, K. The Ngorongoro Crater as the biggest geotouristic attraction of the Gregory Rift (Northern Tanzania, Africa) – geotouristic valorization, touristic development and hazard. Geotourism/Geoturystyka, (24-25), 47. https://doi.org/10.7494/geotour.2011.24-25.47