  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.
