This is Giant Superman 15, published by Mimosa (SA Magazine Co) +/- 1963-1964.
It reprints the cover and all three stories from DC Comics' Adventure Comics 277 (1960):
"The Duel for Earth"
Aquaman: "The Underwater Olympics"
Congo Bill: "The Man-Ape's Mercy Mission"
Also reprinted is this story from DC Comics' Superman's Pal Jimmy Olsen 30 (1958):
"The Cub who cried Wolf"
Also reprinted is thsi story from DC Comics' Action Comics 280 (1961):
Supergirl: "Trapped in Kandor"
48pages, glossy colour cover, black and white newsprint interior.
Here is the cover of issue 15 and DC Comics' original cover: