What song was played during Macías Nguema's infamous execution that took place on Christmas Day in 1969?

Those Were the Days

https://www.reddit.com/r/AskHistorians/comments/6kce00/in_1975_the_president_of_equatorial_guinea/

"Those Were The Days, My Friend" by Mary Hopkins played over an amplifier while soldiers executed 150 people lined up in a stadium on Christmas Day in 1969. The execution took place in Equatorial Guinea.

https://sites.tufts.edu/atrocityendings/2015/08/07/equatorial-guinea/

To clarify, this was one of many executions carried out on the orders of Macías Nguema during his time as the first President of Equatorial Guinea between 1969 and 1979. It is estimated that between 50,000 ad 80,000 people, around 20% of the population, were killed in this time. His own execution after receiving 101 death sentences from a military tribunal was a much less bizarre affair.

https://en.wikipedia.org/wiki/Francisco_Mac%C3%ADas_Nguema