GENERALISED MORPHISMS OF k-GRAPHS: k-MORPHS

@article{Kumjian2007GENERALISEDMO,
  title={GENERALISED MORPHISMS OF k-GRAPHS: k-MORPHS},
  author={Alex Kumjian and David Pask and Aidan Sims},
  journal={Transactions of the American Mathematical Society},
  year={2007},
  volume={363},
  pages={2599-2626}
}
In a number of recent papers, (k + l)-graphs have been constructed from k-graphs by inserting new edges in the last l dimensions. These constructions have been motivated by C � -algebraic considerations, so they have not been treated systematically at the level of higher-rank graphs themselves. Here we introduce k-morphs, which provide a systematic unifying framework for these various constructions. We think of k-morphs as the analogue, at the level of k-graphs, of C � -correspondences between… 
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