2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/138335We employ Hirzebruch-type invariants obtained from iterated p-covers to investigate concordance of links and string links. We show that the invariants naturally give various group homomorphisms of the string link concordance group into L-groups over number fields. We also obtain homomorphisms of successive quotients of the Cochran-Orr-Teichner filtration. As an application we show that the kernel of Harvey's $ρ_n$-invariant is large enough to contain a subgroup with infinite rank abelianization, modulo local knots. As another application, we show that recently discovered nontrivial 2-torsion examples of iterated Bing doubles lying at an arbitrary depth of the Cochran-Orr-Teichner filtration are independent over $\Z_2$ as links, in an appropriate sense. We also construct similar examples of infinite order links which are independent over $\Z$.28 pages, 4 figuresGeometric Topology57M25; 57M27; 57N70text