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Wilfried Imrich (born May 25, 1941) is an Austrian mathematician working mainly in graph theory. He is known for his work on graph products, and authored the books Product Graphs: Structure and Recognition (Wiley, 2000, with Sandi Klavžar), Topics in graph theory: Graphs and their Cartesian Products (AK Peters, 2008, with Klavžar and Douglas F. Rall), and Handbook of Product Graphs (2nd ed., CRC, 2011, with Klavžar and Richard Hammack).