The map of the front lines around Sarajevo is based on UN maps produced at the time. It's possible that they are incorrect in detail as it has not been possible with the available resources to establish the exact position of the front lines. The UN maps are not readily available but you can find other useful maps at the University of Texas library online resource.
Balkans war: A brief guide
The data for the monthly death toll has come from the Istrazivacko Dokumentacioni Centar Sarajevo (research and documentation centre in Sarajevo). These figures have been produced after extensive research of local and international records and corroborated by other documentary evidence. You can find more details at their website.
Photo credits: Getty/AFP