The Open Budget Initiative has just published some working papers
http://internationalbudget.org/what-we-do/major-ibp-initiatives/open-budget-initiative/obi-research/working-papers/IBP Working Paper 1: Budget Transparency and Financial Markets by Farhan Hameed
IBP Working Paper 2: Mineral Wealth and Budget Transparency by Michael Ross
IBP Working Paper 3: Political Determinants of Fiscal Transparency by Joachim Wehner, London School of Economics and Political Science, and Paolo de Renzio, International Budget Partnership and University of Oxford
IBP Working Paper 4: Budget Transparency and Development Outcomes and Rights by Sakiko Fukuda-Parr, the New School, Patrick Guyer, Social Science Research Council, and Terra Lawson-Remer, the New School
Comrades or Culprits? Donor Engagement and Budget Transparency by Paolo de Renzio, International Budget Partnership and University of Oxford, and Diego Angemi
I haven't read them, er, yet and I'll try and put them in the bibliography, er, soon