West's Tax Law Dictionary by Tax research focuses primarily on the Internal Revenue Code and the various primary and secondary materials that interpret it. A tax problem can be complex because it often involves legislative, judicial, and administrative interpretations. Administrative sources play an especially important role in tax research, so understanding the numerous regulations and IRS pronouncements that exist, as well as each one's binding or persuasive authority, is essential.
There are a number of specialized tools to help make tax research more efficient. Looseleaf services or their equivalent electronic version are often a good place to start since they are up-to-date and bring together all relevant primary materials along with commentary and analysis. Tax treatises are also helpful for gaining subject matter familiarity. Wherever you start, tax research requires a thorough, logical, and comprehensive approach.
Federal Income Tax Law: A Legal Research Guide by 
Federal Tax Research: Guide to Materials and Techniques by 
International Tax Law by 
Inside Tax Law: What Matters and Why by 
Federal Income Taxation by 
The Oxford Introductions to U.S. Law: Income Tax Law by 
Federal Income Taxation of Individuals in a Nutshell by 
Tax Procedure and Tax Fraud in a Nutshell by This interactive CALI Lesson covers the legislative, administrative, and judicial materials used in the specialized area of tax law. It can be accessed through your smartphone or tablet, as well as through your computer.
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