The Russian Jewish Encyclopedia entry both Russian-language mirrors cite as their source confirms only the institution and the 1945 start date, not the department name, teaching title, or end date

feldbaumsource-provenanceverificationinstitutional-history

Both Russian Wikipedia and Cyclowiki name "Российская Еврейская Энциклопедия" [Russian Jewish Encyclopedia] as a source for their entries on Fel'dbaum (claim-feldbaum-russian-mirrors-split-professorship-1945-1961-teaching-1945-1964). Read directly, that entry is far terser than either mirror: "С 1937 работал во Всес. эл.-техн. ин-те, с 1945 – в Воен. арт. академии им. Ф.Э.Дзержинского в Москве. С 1961 рук. лаб. самонастраивающихся систем в Ин-те автоматики и телемеханики" — "From 1937 he worked at the All-Union Electro-Technical Institute; from 1945, at the Dzerzhinsky Military Artillery Academy in Moscow. From 1961, head of the Laboratory of Self-Adjusting Systems at the Institute of Automation and Telemechanics."

It confirms the institution and the 1945 start year, and independently corroborates 1961 as the year Fel'dbaum's primary post changed — but it names no department, no "missile control systems" or "rocket control systems" title, and no 1964 or other end date for the academy tenure. The specific, load-bearing phrase the professorship question turns on is absent from the one named tertiary source its own Wikipedia-family mirrors cite for the surrounding facts. The phrase's actual origin — a fuller print edition, an academy personnel record, or an editor's own inference from "Faculty of Reactive Armament" — was not traced this session.