Databases which require an Oxford SSO
Sources on the web available to all with access to the internet
Official sites of national governments
The following may be a useful way of identifying what tax treaties a particular nation has - before tracking the full text on an official website
Schwarz on Tax Treaties by 
Klaus Vogel on Double Taxation Conventions by 
The Impact of the OECD and UN Model Conventions on Bilateral Tax Treaties by 
A Multilateral Tax Treaty: Designing an Instrument to Modernise International Tax by Subject search terms to use in SOLO to find ebooks and e-journals and aarticles available to holders of an Oxford SSO>
Double taxation -- Treaties
Taxation -- Law and legislation
Tax administration and procedure -- International cooperation
International business enterprises -- Taxation -- Law and legislation
Subject search terms to use in SOLO:
Double taxation -- Treaties
Taxation -- Law and legislation
Tax administration and procedure -- International cooperation
International business enterprises -- Taxation -- Law and legislation
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