Trade disputes often involve an analysis of whether certain products are 'like products' in comparison with each other. The 'like products' conception in trade regimes plays a vital role in regulating the coverage of various international trade law obligations. The WTO covered agreement includes many provisions concerning "Like Products". Please interpret the concept of "Like Products" considering the WTO provisions such as MFN Principle, National Treatment Principle, Anti-dumping Law, and Regional Trade Agreements. Include all these FOUR areas while analyzing "Like Products". Must include relevant case references and WTO and other relevant agreements in the answer.