@article{10_1017_S0017089500002184,
     author = {Feinerman, Robert P. and Kelman, Robert B.},
     title = {The convergence of least squares approximations for dual orthogonal series},
     journal = {Glasgow mathematical journal},
     pages = {82--84},
     year = {1974},
     volume = {15},
     number = {1},
     doi = {10.1017/S0017089500002184},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500002184/}
}