Quivers, request for theorem of Dlab & Ringel of 1973

Question

Looking at Gabriel's theorem on Wikipedia page I found the following statement.

Dlab & Ringel (1973) found a generalization of Gabriel's theorem in which all Dynkin diagrams of finite-dimensional semisimple Lie algebras occur.

The reference point to a book which is not available and that I couldn't find. Does anybody know the statement which Wikipedia is referring to? Thanks

Answer 1

A better reference might be the following:

Dlab, V.; Ringel, C.M. Indecomposable representations of graphs and algebras. Mem. Amer. Math. Soc. 1976, 6, v+57.

Also, the article Valued Graphs and the Representation Theory of Lie Algebras by Joel Lemay discusses this result.