Update users_comments.md

Author: AtsushiSakai

users_comments.md

@@ -409,6 +409,9 @@ URL: https://arxiv.org/abs/1910.01557
 8. Hahn, Carsten, et al. "Dynamic Path Planning with Stable Growing Neural Gas." (2019).
 URL: https://pdfs.semanticscholar.org/5c06/f3cb9542a51e1bf1a32523c1bc7fea6cecc5.pdf
 
+9. Brijen Thananjeyan, et al. "ABC-LMPC: Safe Sample-Based Learning MPC for Stochastic Nonlinear Dynamical Systems with Adjustable Boundary Conditions"
+URL: https://arxiv.org/pdf/2003.01410.pdf
+
 # Others
 
 - Autonomous Vehicle Readings https://richardkelley.io/readings