Mladen Plisic, Milan Spoljaric and Mladen Kulisic climbed the 6,962-metre peak in the Andes in extremely low temperatures, sinking below minus 40 degrees Celsius.
The other three members of the expedition, Dane Simic, Tomislav Stedul and Tomislav Canic, had to return to their start base due to altitude sickness.
The expedition had started on January 25.