@misc{Goebel_Kazimierz_A,
 author={Goebel, Kazimierz and Takahashi, Wataru},
 howpublished={online},
 publisher={nakł. UMCS},
 language={eng},
 type={artykuł},
 title={A note on mappings with nonexpansive square},
 keywords={matematyka},
}