@article{TM2_2013_XVI_1_a3,
     author = {Aaron Melman},
     title = {A somewhat unexpected concavity},
     journal = {The Teaching of Mathematics},
     pages = {18 },
     publisher = {mathdoc},
     volume = {XVI},
     number = {1},
     year = {2013},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TM2_2013_XVI_1_a3/}
}