- University of Haifa
- Norwegian University of Life Sciences
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- University of Tennessee, Knoxville
- Xi'an Technological University
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- University of Oklahoma
- Tulane University
- Langston University
- Texas Tech University
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- Tulane University
- Langston University
- Texas Tech University
- University of Oklahoma
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- Victoria University of Wellington
- Universidade de São Paulo
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- University of Tennessee, Knoxville
- University of Montana
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- Institute of Mathematics of the Polish Academy of Sciences
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- Norwegian University of Life Sciences
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- Technion-Israel Institute of Technology
- ETH Zürich
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- University of Tennessee, Knoxville
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- Pittsburg State University
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- University of Milan
- Ca' Foscari University of Venice
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