What four geyers are located in the Upper Geyer Basic of Yellowstone National Park ?
Geyer was also the problematic hero of one of Gerhart Hauptmann 's major plays , the historical drama " Florian Geyer " , published in 1896 , and the inspiration for the German folk song , " Wir sind des Geyers schwarzer Haufen " ( " We are Geyer 's Black Band " ) , which has been adopted by the international Marxist labour movement as a rousing union anthem .