After stating several tools which can be used to construct indecomposable
tree modules for quivers without oriented cycles, we use these methods to
construct indecomposable tree modules for every imaginary Schur root. These
methods also give a recipe for the construction of tree modules for every root.
Moreover, we give several examples illustrating the results.Comment: Typos corrected; references added; deleted former Lemma 3.13 which is
not neede
