Olsder's own 2003 CV attests a University of Twente tenure of 1971–1981, ahead of Hollandse Signaalapparaten (1981–1983) and a 1983 TU Delft professorship

geert-jan-olsderhuibert-kwakernaakuniversity-of-twentecontrol-theorycold-war-sciencenetherlands

A brief curriculum vitae dated 6 October 2003, published by Geert Jan Olsder on his own TU Delft staff page, gives his career in his own words: born 1 January 1944 in Muntendam, the Netherlands; M.Sc. (1968) and Ph.D. (1971), "both with honors," in applied mathematics at Groningen University, the Ph.D. thesis "about time-optimal control with applications in ship-maneuvering"; then "From 1971-1981 he was employed at Twente University of Technology, from 1981-1983 at Hollandse Signaalapparaten ... In 1983 he was appointed (full) professor of Mathematical System Theory at Delft University of Technology." The same CV dates his research interests moving "from optimal control (1968-1975) to dynamic game theory (1973-1985)" — placing him in optimal-control work, not yet game theory, through 1975.

This is the primary that resolves a lead the vault had carried only as a search snippet. claim-olsder-twente-group-member-until-1982 records that the 2025 Kwakernaak obituary — a Tier-2 secondary — names Olsder as a Twente group member "(till 1982)," and its own audit flagged this CV as an unconfirmed route that "defeated every direct-fetch route" an earlier session tried. Read directly here, the CV gives Olsder's first-person employment span as 1971–1981, one year short of the obituary's parenthetical "(till 1982)." As Olsder's own account of his own employment dates, the CV is the stronger source for the endpoint; the obituary's "(till 1982)" is a colleague's later recollection of group membership, which need not coincide to the year with a formal employment end. Either way the span covers the 1976 Olsder–Strijbos population-planning paper and the 1978 Helsinki IFAC congress (claim-olsder-eyewitness-account-confirms-song-jian-at-1978-helsinki-ifac-congress), the two events the vault anchors to his Twente years. (On his later university-level role, the CV itself states "Since 1998 he has been deputy vice-chancellor of the university"; the 1999–2008 vice-rectorship span circulating in Tier 3–4 aggregators is not established here.)