Abstract
It is shown that for every compositionτ of morphisms and inverse morphisms there exist morphismsh 1,h 2,h 3, andh 4 such that\(\tau = h_4^{ - 1} \circ h_3 \circ h_2^{ - 1} \circ h_1 \). This solves a problem raised by Latteux and Leguy [5] and partially solved by Turakainen [8], [9].
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Latteux, M., Turakainen, P. A new normal form for the compositions of morphisms and inverse morphisms. Math. Systems Theory 20, 261–271 (1987). https://doi.org/10.1007/BF01692069
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DOI: https://doi.org/10.1007/BF01692069