Kosningafræðarinn. Kjördæmaskipan og aðferðir við úthlutun sæta

The author of the main text of this, mathematician Þorkell Helgason, has been giving advice to Icelandic governments for decades when it comes to election systems. Both municipality and parliament elections. Here he explains the calculations involved and pros and cons of the choices each government faces. 

The book also covers what reforms might be necessary for the future and criticism towards the elections system.