which bishops had their full birth dates and death dates listed?
geir vidalin, helgi thordersen, 'petur petursson, hallgrimur sveinsson, thorhallur bjarnarson, sigurgeir sigurdsson, asmundur gudmundsson, sigurbjorn einarsson, olafur skulason
of those which ones were in office before 1900?
geir vidalin, helgi thordersen, 'petur petursson
who of these was not born in the fall?
helgi thordersen