GT Grossberg, Manes F, RF Allegri, et al..  The Safety, Tolerability, and Efficacy of Once-Daily Memantine (28 mg): A Multinational, Randomized, Double-Blind, Placebo-Controlled Trial in Patients with Moderate-to-Severe Alzheimer’s Disease Taking Cholinesterase Inhibitors. CNS spectrums 2013 27: 469-78

The Safety, Tolerability, and Efficacy of Once-Daily Memantine (28 mg): A Multinational, Randomized, Double-Blind, Placebo-Controlled Trial in Patients with Moderate-to-Severe Alzheimer’s Disease Taking Cholinesterase Inhibitors.