@article{AMI_2013_42_a0,
     author = {Antal Bege and J\'ozsef Bukor and J\'anos T. T\'oth},
     title = {On (log-) convexity of power mean},
     journal = {Annales mathematicae et informaticae},
     pages = {3--7},
     publisher = {mathdoc},
     volume = {42},
     year = {2013},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AMI_2013_42_a0/}
}