Melodiya's own booklet for the CD reissue MEL CD 10 02359 (2015), included with the rip as 9899edc0b4a9901ea21bb6ca6d816628.pdf, states the recording date in all three of its languages: "Запись 1974 г." / "Recorded in 1974." / "Enregistrement effectué en 1974." The year here was 1976, which is what operadis gives (http://www.operadis-opera-discography.org.uk/CLPUTOSC.HTM entry 154, "1976(STU) - Ermler Mark - Bolshoi Theatre") -- but operadis lists only the Melodiya LP issue С10 8431/6 for it, and a Melodiya С10-08xxx number is a 1976-77 issue, so 1976 looks like the release year. The label's own statement of when the recording was made is the better source for a recording year.