diff --git a/nass-fem.bib b/nass-fem.bib
index b0c8e4c..ebeefb9 100644
--- a/nass-fem.bib
+++ b/nass-fem.bib
@@ -178,6 +178,25 @@
 
 
 
+@article{yang19_dynam_model_decoup_contr_flexib,
+  author          = {Yang, XiaoLong and Wu, HongTao and Chen, Bai and Kang,
+                  ShengZheng and Cheng, ShiLi},
+  title           = {Dynamic Modeling and Decoupled Control of a Flexible
+                  Stewart Platform for Vibration Isolation},
+  journal         = {Journal of Sound and Vibration},
+  volume          = 439,
+  pages           = {398-412},
+  year            = 2019,
+  doi             = {10.1016/j.jsv.2018.10.007},
+  url             = {https://doi.org/10.1016/j.jsv.2018.10.007},
+  issn            = {0022-460X},
+  keywords        = {parallel robot, flexure, decoupled control},
+  month           = {Jan},
+  publisher       = {Elsevier BV},
+}
+
+
+
 @article{du14_piezo_actuat_high_precis_flexib,
   author          = {Zhijiang Du and Ruochong Shi and Wei Dong},
   title           = {A Piezo-Actuated High-Precision Flexible Parallel Pointing
diff --git a/nass-fem.pdf b/nass-fem.pdf
index 70ff7d7..784fbb9 100644
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