Alec Kriebel. A modular-storage proof of NP-completeness for chip-firing halting on simple digraphs. Version 1.0, 16 October 2026. Unrefereed preprint.
ORCID: https://orcid.org/0009-0001-9320-500X
License: CC BY 4.0. DOI not assigned at the dated preparation checkpoint.
