@article{10_1017_S0017089500001385,
     author = {Tweddle, I.},
     title = {The extremal points of the range of a vector-valued measure},
     journal = {Glasgow mathematical journal},
     pages = {61--63},
     year = {1972},
     volume = {13},
     number = {1},
     doi = {10.1017/S0017089500001385},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500001385/}
}