An income-tax based on the Pareto Law
Nuut, Jüri
1937
https://www.ester.ee/record=b1492647*est
https://digikogu.taltech.ee/et/Item/14f7e744-2fb9-4cc2-a57b-6e73da8a9a84
Longitude and latitude determinations in Estonia from 1930 to 1933
Livländer, Robert
1937
https://www.ester.ee/record=b1492627*est
https://digikogu.taltech.ee/et/Item/52ef8990-7f97-49d6-8bbd-477b954bd14f