Eine Bemerkung zu einigen $2$-dimensionalen Komplexen, die im ${\mathbb{R}}^4$ fast-eingebettet werden können

We observe that many of the 2-complexes constructed by Freedman-Krushkal-Teichner in their paper on the incompleteness of the van Kampen embedding obstruction can actually be PL immersed in ${\mathbb{R}}^4$ in such a way that the images of the interiors of distinct cells are disjoint. In other words, they PL almost-embed in ${\mathbb{R}}^4$ with singularities occurring only as self intersections of some 2-cells. This note is written in (not necessarily modern) German.