TY - JOUR AU - TI - Asymptotically Efficient Estimation of Covariance Matrices with Linear Structure JF - The Annals of Statistics DO - 10.1214/aos/1193342389 DA - 1973-01-01 UR - https://www.deepdyve.com/lp/unpaywall/asymptotically-efficient-estimation-of-covariance-matrices-with-linear-L4GZKxigTP DP - DeepDyve ER -