Linearized ADMM Converges to Second-Order Stationary Points for Non-Convex Problems Temporal Parallelization of Inference in Hidden Markov Models Editorial A (Belated) Message From the New EiC A Robust Wavenumber-Domain Superdirective Beamforming for Endfire Arrays On the Convergence Behavior of Partitioned-Block Frequency-Domain Adaptive Filters Identifiability-Guaranteed Simplex-Structured Post-Nonlinear Mixture Learning via Autoencoder EDICS Information for Authors 4859-4874 4875-4887 4888-4889 4890-4905 4906-4920 4921-4936 www.signalprocessingsociety.org [3] OCTOBER 2021