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By Ammar Khanfer. Ammar Khanfer earned his Ph.D. from Wichita State University, USA. He also works on the qualitative theory of differential equations, and in the area of inverse problems of mathematical physics.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.