@article{MS2_1971__29_166218,
     author = {H.G. Diamond and F. Albrecht},
     title = {An {Extremal} {Problem} {Involving} {Functions} and {Their} {Inverses.}},
     journal = {Mathematica Scandinavica},
     pages = {328--336},
     publisher = {mathdoc},
     volume = {29},
     year = {1971},
     zbl = {0235.49007},
     url = {http://geodesic.mathdoc.fr/item/MS2_1971__29_166218/}
}