Cohn path algebras of higher-rank graphs
  In this article, we introduce Cohn path algebras of higher-rank graphs. We prove that for a higher-rank graph $\Lambda $, there exists a higher-rank graph $T\Lambda $ such that the Cohn path algebra of $\Lambda $ is isomorphic to the Kumjian-Pask algebra of $T\Lambda $. We then use this isomorphism and properties of Kumjian-Pask algebras to study Cohn path algebras. This includes proving a uniqueness theorem for Cohn path algebras. 
Lisa Orloff Clark and Yosafat E. P. Pangalela
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