Notes, Comments and Preliminary results Dec 30 2025 Prince Fosu and Kevin Sylwester   Environmental tax revenue and public health care expenditure   Abstract  Contact Information  Citation  Full Text  -  Note   Sep 30 2025 Maïga Nouhoun Oumarou   Analysis of public sector efficiency in Sub-Saharan Africa: Focus on economic performance and stability   Abstract  Contact Information  Citation  Full Text  -  Preliminary Result   Dec 30 2024 Frank Daumann and Julian A Klöcker   International migration and the transfer system: A method to limit brain drain and excessive use of the welfare state   Abstract  Contact Information  Citation  Full Text  -  Preliminary Result