@misc{10_1017_S0017089500002408,
     title = {The {Convergence} of {Least} {Squares} {Approximations} for dual {Orthogonal} {Series{\textdagger}}},
     journal = {Glasgow mathematical journal},
     pages = {184--184},
     year = {1974},
     volume = {15},
     number = {2},
     doi = {10.1017/S0017089500002408},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500002408/}
}