Does Kwakernaak's own 1977 paper ('Application of control theory to population policy') cite Åström's work directly?
The question
observation-greenhalgh-kwakernaak-kaelbling-astrom-bipartite-pairing-is-confirmed-feldbaum-bridge rules that Kwakernaak and Åström share only a common ancestor (A.A. Fel'dbaum), not a direct connection — "neither Kwakernaak and Åström, nor Song Jian and Kaelbling/Littman/Cassandra, show any direct connection in any source read this session or elsewhere in the vault." That verdict has never been checked against the single most direct possible test: Kwakernaak's own 1977 paper, "Application of control theory to population policy" (in A. Bensoussan & J.L. Lions, eds., New Trends in Systems Analysis, Springer LNCIS, 1977, pp. 359-378, DOI 10.1007/BFb0041123), remains unread by any vault session — Springer paywalls the chapter. Whether Kwakernaak cites Åström's optimal-control or Markov-decision work in his own bibliography is the one check that could turn the "common ancestor, not direct link" verdict into a genuine direct link.
Why it matters
The "shared ancestor, not horizontal link" finding is the load-bearing conclusion of the confirmed-bridge observation note above — it is what keeps the bridge a two-hop genealogy rather than a one-hop citation. The claim currently rests on absence of evidence (no source read so far shows a direct citation), not on a direct read of the one document positioned to settle it either way.
What would answer it
- A direct read of Kwakernaak's 1977 chapter (DOI 10.1007/BFb0041123) via
extract_pdfor a library route, checked for any citation of Åström, "optimal control of Markov processes," POMDP-adjacent vocabulary, or Fel'dbaum himself in its own reference list. - Negative confirmed only by a full reference-list read, not a search summary, per the quote-provenance rule.
Provenance
Raised from the promotion of 10-inbox/raw/2026-09-18-recovered-bipartite-hop-does-greenhalghs-kwakernaak-in-song-0ddc78.md (2026-10-02, headless), which flagged this exact gap [unverified-mechanism — needs primary] while checking (and rejecting) a different, now-settled lead — see claim-kwakernaak-did-not-coedit-automatica-1995-system-identification-special-issue.
Progress log
- 2026-10-02: raised, unanswered. Springer paywall is the known blocker; no library route available per sources.md (Cali, 2026-10-01: "not right now").
- 2026-10-06: answered via CrossRef's deposited reference-list metadata for the chapter's DOI (10.1007/BFb0041123) — a workaround for the still-paywalled chapter text. Complete 13-item reference list contains no Åström (or Fel'dbaum) citation; see
answered_logabove and claim-kwakernaak-1977-bibliography-excludes-astrom-rests-on-dutch-twente-club-of-rome-lineage.
Progress log
- 2026-10-06 — claim-kwakernaak-1977-bibliography-excludes-astrom-rests-on-dutch-twente-club-of-rome-lineage settles it: CrossRef's deposited metadata for the chapter's DOI gives its complete 13-item reference list, and none of the 13 entries names Åström (or Fel'dbaum). What settled it: the publisher's own structured bibliography record, not a search summary — a document-level negative, not an inference from absence elsewhere. Residual caveat (why the claim-note stays
status: seedlingwith an[unverified-mechanism]flag): this is CrossRef's deposited metadata, not a direct read of the chapter's own printed reference pages, since Springer, ResearchGate, and Twente's repository all blocked direct access this session. The question's headline — is there a direct citation? — is answered (no); the stricter 'read the printed pages themselves' standard remains open as a residual, not reopened as a live doubt.