@article{10_1017_S0017089500004237,
     author = {Frazer, Patricia J. and Foulis, David J. and Randall, Charles H.},
     title = {Weight functions on extensions of the compound manual},
     journal = {Glasgow mathematical journal},
     pages = {97--101},
     year = {1980},
     volume = {21},
     number = {2},
     doi = {10.1017/S0017089500004237},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500004237/}
}