@article{ChangphasDenecke2005,
  author    = {Changphas, Thawhat and Denecke, Klaus-Dieter},
  title     = {Green's relation R on the monoid of clone endomorphisms},
  issn      = {1005-3867},
  year      = {2005},
  abstract  = {A hypersubstitution is a map which takes n-ary operation symbols to n-ary terms. Any such map can be uniquely extended to a map defined on the set W-tau(X) of all terms of type tau, and any two such extensions can be composed in a natural way. Thus, the set Hyp(tau) of all hypersubstitutions of type tau forms a monoid. In this paper, we characterize Green's relation R on the monoid Hyp(tau) for the type tau = (n, n). In this case, the monoid of all hypersubstitutions is isomorphic with the monoid of all Clone endomorphisms. The results can be applied to mutually derived varieties},
  language  = {en}
}
@article{ChangphasDenecke2003,
  author    = {Changphas, Thawhat and Denecke, Klaus-Dieter},
  title     = {Green's Relations on the Seminearring of Full Hypersubstitutions of Type (n)},
  year      = {2003},
  language  = {en}
}
@article{ChangphasDenecke2003,
  author    = {Changphas, Thawhat and Denecke, Klaus-Dieter},
  title     = {Complexity of Hypersubstitutions and Lattices of Varieties},
  year      = {2003},
  language  = {en}
}
@article{DeneckeChangphas2003,
  author    = {Denecke, Klaus-Dieter and Changphas, Thawhat},
  title     = {Full hypersubstitutions and fully solid varieties of semigroups},
  year      = {2003},
  language  = {en}
}
@phdthesis{Changphas2004,
  author    = {Changphas, Thawhat},
  title     = {Monoids of Hypersubstitutions},
  address   = {Potsdam},
  pages     = {vii, 88 S.},
  year      = {2004},
  language  = {en}
}
@article{Changphas2006,
  author    = {Changphas, Thawhat},
  title     = {The order of hypersubstitutions of type tau = (3)},
  issn      = {1005-3867},
  year      = {2006},
  abstract  = {Hypersubstitutions were introduced in [3] as a way of making precise the concepts of hyperidentity and M- hyperidentity. The monoid of hypersubstitutions has been widely studied by many authors. Knowledge of the monoid of hypersubstitutions can be applied to the concept of M-hyperidentities. In this paper, we show that the order of hypersubstitutions of type tau = (3) is 1, 2, 3 or infinite},
  language  = {en}
}