L. Pontrjagin (1934), Annals of Mathematics 35(2):361–388 — DOI-10.2307/1968438
Standing in the record
Registered on 2026-09-29 at the owner’s request, because the owner’s prior-art novelty map (a private working document on concepts as projectors, the linear representation hypothesis and their neighbours) cites it: row 7 and §2 item 2: the Pontryagin leg of the duality tripod (characters). It is seeded from metadata and published descriptions and has not been read here.
The map names this reference only loosely; this entry is one reasonable reading of it, and the choice is the owner’s to revise.
Identification notes: Program name. Chosen the English Annals paper (1934), the standard citation; the result was also announced in Pontryagin 1934 C. R. and extended to locally compact groups by van Kampen 1935. Crossref spells “Pontrjagin”.
It was filed Deferred, unread. NOTE-284 is the close reading of 2026-09-29, and it placed the work: Active — worth reading as the primary source of Pontryagin duality in its compact/discrete form, and it is careful and self-contained given Peter–Weyl and Haar. For the full locally compact abelian duality (each LCA group is the dual of its dual), van Kampen (1935) and later textbook treatments supersede it.