@article{AFM_1987_12_1_a5,
     author = {T. Kilpel\"ainen},
     title = {Convex increasing functions preserve the {sub-F-extremality}},
     journal = {Annales Fennici Mathematici},
     pages = {55--60},
     publisher = {mathdoc},
     volume = {12},
     number = {1},
     year = {1987},
     doi = {10.5186/aasfm.1987.1216},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.5186/aasfm.1987.1216/}
}