@article{10_4153_CJM_1968_033_x,
     author = {Robertson, James B.},
     title = {Orthogonal {Decompositions} of {Multivariate} {Weakly} {Stationary} {Stochastic} {Processes}},
     journal = {Canadian journal of mathematics},
     pages = {368--383},
     year = {1968},
     volume = {20},
     number = {1},
     doi = {10.4153/CJM-1968-033-x},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1968-033-x/}
}