Vanja Stojković is a prolific Yugoslavian singer and lyricist, who writes the lyricis to most of her covers.
In 1968 she released an EP called O, samo ti and the last track on Side B is called Volite jedan drugog (which translates into "You love one another"").
It is supposedly written by Greek super composer Mikis Theodorakis.
Here is the YouTube video:
A typical Theodorakis song, but which one?