Åström's 1965 Notes and reference list cite exactly one Fel'dbaum work, the 1962 Markov-objects paper, and none of the 1960 Dual Control Theory papers

control-theoryfeldbaumkarl-astromdual-controlcitation-analysispomdp

Reading the whole Notes and References block of Åström's 1965 paper turns up a single Fel'dbaum entry, reference [13], which the OCR text gives as "On optimal control of Markov objects … Remote Control 24, 993–1007 (1962)." There is no 1960 entry, no "Dual Control Theory" title, and no second Fel'dbaum item. The Fel'dbaum papers that claim-feldbaum-1960-papers-define-dual-control-as-additive-risk-of-action-and-risk-of-study reads are therefore not in Åström's bibliography.

The context of the one citation matters. Åström cites Fel'dbaum in a list of authors who, like Bellman, used Markovian models for control problems (with Florentin, Kolmogorov, Krasovskii and Pontryagin). It is not offered as a source for dual control or for the exploration/exploitation trade-off, and the same Notes credit the foundations of stochastic variational calculus to Bellman.

This sharpens claim-astrom-1965-notes-section-cites-feldbaum-pontryagin-kolmogorov-lineage, which records that the citation exists, by adding what it does not include. It also bears on claim-feldbaum-1960s-dual-control-formalized-exploration-exploitation-tradeoff and claim-mainstream-rl-exploration-traces-to-1933-bandit-lineage-not-feldbaum-dual-control: the person-level link from Fel'dbaum to Åström stands, but no document-level path from the 1960 papers to Åström's POMDP formulation appears in Åström's own references.

Scope limit: see watch_flag. The bibliography line is OCR-garbled ("Freppaum, A. a …"); the author reading as Fel'dbaum rests on the surrounding "Feldbaum {13}" in the Notes.