Guannan Qu Chenkai Yu Steven H. Low Adam Wierman Exploiting Linear Models for Model-Free Nonlinear Control: A Provably Convergent Policy Gradient Approach. 6539-6546 2021 CDC https://doi.org/10.1109/CDC45484.2021.9683735 conf/cdc/2021 db/conf/cdc/cdc2021.html#QuYLW21