Åström's reference [13] matches Fel'dbaum's 1962 Avtomatika i Telemekhanika paper at pp. 993–1007, though Åström prints volume 24 where the archive says 23

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Åström's 1965 reference [13] reads (OCR) "On optimal control of Markov objects. … Remote Control 24, 993–1007 (1962)." The Math-Net.Ru table of contents for Avtomatika i Telemekhanika 1962, vol. 23, issue 8, lists "On optimal control of Markov processes" by A. A. Feldbaum at pp. 993–1007. Year and page range agree; the title differs only in "objects" versus "processes" (a translation choice); the volume differs (24 in Åström, 23 in the archive).

It is a different article from the 1960 pair, "Dual Control Theory. I" (vol. 21, no. 9, pp. 1240–1249) and "II" (vol. 21, no. 11, pp. 1453–1464), whose content is in claim-feldbaum-1960-papers-define-dual-control-as-additive-risk-of-action-and-risk-of-study. Title, year, volume and pages all differ, which is what makes the negative finding in claim-astrom-1965-reference-list-contains-no-feldbaum-1960-dual-control-papers a statement about documents and not just about a person.

The volume mismatch is minor and plausibly a translation-numbering artefact: the Åström entry cites the English Automation and Remote Control, and the archive numbers the Russian original. Comparison against the English translation's own record would settle it. Whether the 1962 paper cites the 1960 papers was not checked. The person bridge to claim-song-jian-studied-under-feldbaum-in-moscow is unchanged.