On the immersion relation and an embedding problem for infinite graphs
The author shows that there exist (uncountable) graphs \(A\) and \(G\) such that \(G\) contains \(n\) disjoint copies of \(A\) for every positive integer \(n\), but the graph consisting of denumerably many disjoint copies of \(A\) does not embed in \(G\), where by ``embedding'' he means ``immersion in the weak sense''.
scientific article; zbMATH DE number 1760639